Need alignment specs. For "69"

[mestorod70]

I would look for another shop.
If the tech cant align a gm muscle car without his computer giving him the numbers
then he is not your guy.
Your info is correct regarding tires.
The old bias ply tires used neg caster...new radials use pos caster.
I would try these.....1/6 toe in.
half a degree neg camber.
Four degrees positive caster.
Some folks run as much pos caster as can be dialed in but 4 should ok.
Perhaps others will chime in here.