Need help with this ahk script.....how to add xbutton1 to activate key 8 & 9

; Title: WoWscripts - Spamming macro hotkeys that Toggle themselves ON and OFF
; author: David J Rosenheim
; date: July 16, 2016
; purpose: Reposition and resize World of Warcraft window as soon as it’s opened
; then setup multiple hotkeys capable of toggling themselves on and off.

/* ChangeLog

0.9.1.0 Beta   Date: 06/22/20  11:36 PM
- rewrote script to simplify defining of hotkeys and to make logic a bit more straight forward
- added logic to detect when special keys are used as hotkeys (i.e. Numpad0 or F1) and to then enclose 
	hotkey name in curly braces "{}" so that SendInput command will send the correct key.

0.9.0.2 Beta   Date: 06/03/20  5:51 PM
- Fixed issue with hotkey continuing to fire repeatedly while Active window is NOT same window loop started in
- added a line that can be uncommented to allow testing hotkeys using windows program Notepad.exe
- added hotkey Ctrl+Alt+R to allow user to quickly Reload this script (needed when chgs made while running)
- added hotkey Ctrl+Win+X to allow user to Immediately terminate this script and unload it from memory

0.9.0.1 Beta   Date: 05/15/20  7:09 PM
- removed WinMaximize and chgd back to WinMove as maximized WoW windows were causing issues when alt-tabbing to other windows
- script defines 2 winProcesses - 1st for World of Warcraft Retail, 2nd for World of Warcraft Classic
- created _winGroup and modified script so that hot keys are context-sensitive to only windows in the Group

0.8.0.1  Beta	Date: 9/03/19  1:09:10 PM
- Changed WinMove to WinMaximize as game window extends beyond left/right side of screen when full height

0.8.0.0  Beta	Date: 9/09/18  3:36:41 PM	
- Added logic that detects if the current Hotkey is the same as previous hotkey
- Changed new behaviour that causing currently running spamming loop to switch to a new hotkey character without toggling OFF first.
- Added _swapHotKeys boolen variable to allow user to turn new "swapping hotkey character" behaviour ON or OFF.

0.7.1.0  Beta	Date: 9/09/18  12:54:14 PM	
- small number of updates to some comments to make logic more clear

0.7.0.0  Beta	Date: 8/11/16  11:26:26 PM
- Moved main code to SpamHotKey label so that multiple hotkeys can be processed using the same code
- changed method of defining hotkeys from double-colon to Hotkey command
- changed method of specifing context-sensitivity for hotkeys from "#If WinActive(" to "Hotkey, IfWinActive"
- #MaxThreadsPerHotkey is now 2 instead of 1 and is only defined under the SpamHotKey label
- Now parsing A_ThisHotkey to get the keystroke for the SendInput command.  Parsing removes "$", if first character.
	Since a hotkey's modifiers (ctrl,alt,shift) are included in its name, parsing A_ThisHotkey ensures that the
	modifiers will be included as part of the keystroke sent by the SendInput command.
- Suspend hotkey is now working correctly
- all hotkeys (including Suspend hotkey) are correctly context-sensitive and only working in the _winProcess window. 

*/

#NoEnv ; Recommended for performance and compatibility with future AutoHotkey releases
#Warn ; Enable warnings to assist with detecting common errors
SendMode Input ; Recommended for new scripts due to its superior speed and reliability
SetWorkingDir %A_ScriptDir% ; Ensure a consistent working directory by making script unconditionally use its own folder

_keepFiring := False ; whether to keep spamming hotkey or not
_prevHK := “” ; Previous hotkey (needs to be global so 2nd thread sees what hotkey 1st thread is spamming)
_swapHKs := True ; true = Press same hotkey to toggle OFF; otherwise, switch to new hotkey and keep spamming
; false = Pressing any hotkey toggles OFF current spamming hotkey

_notepad := “ahk_exe notepad.exe”
;GroupAdd, _winGrp, % _notepad ; uncomment for testing and debugging using Notepad
GroupAdd, _winGrp, ahk_exe Wow.exe ; add this process to Group
GroupAdd, _winGrp, ahk_exe WowClassic.exe ; add this process to Group

; Only continue after any window in Group becomes Active
WinWaitActive, ahk_group _winGrp
; move and resize the active window
if WinActive(_notepad)
WinMove, , 150, 150, 1000, 650 ; chg x,y,width,height to match preference for Notepad ;
else
WinMove, , -7, -9, 1933, 1049 ; chg x,y,width,height to match preference for WoW game client

#MaxThreadsPerHotkey 2 ; 2 threads are needed so that hotkey loop can be interrupted
#MaxThreadsBuffer On ; while loop running, allows 2nd hotkey to be buffered instead of ignored
#IfWinActive, ahk_group _winGrp ; make following hotkeys context-sensitive (i.e. only work in Group windows)
^!s::Suspend ; Ctrl+Alt+S - Toggles ON/OFF the Suspend function for all hotkeys
^#x::ExitApp ; Ctrl+Win+X - Immediately terminate this script and unload it from memory
$8::
$9::
$Numpad5::
Gosub, SpamHotKey ; rapidfire hotkeys ("$" in front prevents SendInput cmd from triggering hotkey again)

return

SpamHotKey:
_thisHK := A_ThisHotkey

If SubStr(_thisHK,1,1) = “$”
_thisHK := SubStr(_thisHK,2) ; trim “$” char from beginning of hotkey name
if StrLen(_thisHK) > 1 ; If length of hotkey name is greater than 1, then
_thisHK := “{” . _thisHK . “}” ; hotkey is special keyname and must be enclosed in curly braces

; If this is 1st thread, start loop that sends hotkey until toggled OFF
If NOT _keepFiring {
_keepFiring := true
_prevHK := _thisHK
_thisID := WinActive(“A”) ; get Active Window’s unique ID nbr (HWND)
Loop { ; this loop keeps running until 2nd thread signals to stop spamming any hotkey
if NOT WinActive(“ahk_id” . _thisID) ; if NOT same window as when this loop started, then…
WinWaitActive, ahk_id _thisID ; pause loop here and wait for original window to become Active again
sendinput, %_thisHK% ; send the hotkey pressed
sleep 100 ; speed of clicks… smaller=faster, larger=slower
if not _keepFiring ; If 2nd thread signaled for this loop to stop spamming hotkey, then…
break ; Break out of this loop
}
}
Else { ; … this is 2nd thread and 1st thread is already running its loop
If (_thisHK = _prevHK or _swapHKs = False) ; if hotkey same as previous hotkey OR no swapping hotkeys, then…
_keepFiring := false ; Signal 1st thread to stop looping
else ; otherwise, keep loop running and now spam new hotkey
_prevHK := _thisHK
}

return ; Ends thread. If this is 2nd thread, 1st thread will resume looping and see any changes made

Can some one help just how to put xbutton1 to active 8 & 9…thanks