if i wanted to make my 1990 3.1 turbo'd, where would i pull my vacuum from? also if i intend to go big on the turbo & not run a lot of psi (id be happy to encourage lag, just want 4200rpm+ power) will i have to run an intercooler?

Pull your vacuum? Just intake vacuum. Yes run an intercooler. No dont put a rediculous turbo on it. These engines make no power after about 4500 rpms. These 3.1s love 2000-3500 rpms. Smaller turbo will work great, shit just use a stock TGP setup, be the easiest route.  If you dont run an intercooler your going to ping like crazy and power wont be so great.

+1 on that answer.