[mr48chev]

I'd think that you need around 1/8 inch toe in. I've never seen a rear wheel drive vehicle that was street driven that didn't need some toe in although different rigs react to the amount you put in differently.

Scroll down to page 104 the factory calls for .132 to .219 toe in on a 55 second series 3100 with 3 degrees caster at designed weight and 5 degrees at curb weight meaning that ready to drive it should have closer to 5 degrees with camber I can't decode. https://www.gmheritagecenter.com/doc...2nd-Series.pdf

When I was aligning front ends for a living I always started with the factory specs for a certain vehicle and then tweaked the settings if I needed to go get it to drive down the road right
I had my test drive loop that I test drove every rig I aligned in the dealership I worked in to make sure that they tracked straight and the steering wheel was centered. That reduced come backs on alignments to almost 0 as I seldom had a customer not like the way a rig drove.

A bit more caster is sometimes desirable for tracking at high speeds but can be a royal pain at real low speeds as you are fighting the extra caster when you turn the steering wheel.