'66 Slant Six Turbo Build

Wideband is a must and your going to need a tach as far as a base line tune I'd start with around 72 jet size and a 6.5 power valve I wouldn't worry about trying to make a brpv till you start pushing in the teens psi of boost
I have 72 in my 650 on the primary metering block and 82 in the rear but I haven't had much tuning time because of the colder weather here in the north.
Set your fuel pressure to 6 psi and just tune from there
Good luck
Aaron