I'm not aware of any online *free* source that could supply you with the schematics to be downloaded.
Alldata would be the most recognized online source but one has to buy a subscription to the service.
https://www.ebay.com/itm/314081709204?_skw=grand+prix+service+manuals&itmmeta=01J80R0NQYEA2W7F0QPRY834E9&hash=item4920ba8c94:g:~D4AAOSwna9iuiRv
$110 US...money well spent....and you'll have them forever.