Alright this is my first time doing this so I'm not well informed on the subject.
For example I don't know what my options are for pickups and bridges or
even necks.

The project:
1980's Peavey T-15 (American)

What I want:
Seymour Duncans if possible (id really like the SH1 59 model)
Floyd Rose bridge/tune lock on top of neck (likely spendy )
Stain it? or sand and refinish
a new neck
custom pickguard (black transparent plexiglass)

Tell me what you guys think, and if you know anything about building a guitar
I'll take all the tips I can get!
I think you should have kept it how it was. Maybe, at the most just stain it, but the Peavey pickups make it natural and how it came with. It keeps it vintage. you dont really want to mod a vintage guitar.