Hey, welcome to the site.
Looks like you have a pretty specific question regarding a wiring radio diagram. Unfortunately you won't get your answer in this section.
I would suggest using the search function first and foremost. If you don't get any results from that, try posting in the "Audio,Security and Visual Electronics" Section, or better yet, under the "Other W-body Specific" area, go into the section "Pontiac Grand Prix" .
You have what is commonly referred to as a "pre-gen". That just means you have a GP that is before the 97-03 generation.
