Rich, Welcome to the "Bolt" you didn't say what year your truck is so I would only be guessing on tire size. Timing I would guess at 4-6 degrees BTDC should get you started. Google "Service Manual" for your year truck and you should get several thousand options for buying one! Good luck with your project.

Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
Support those brave men/women who stand the "Thin Blue Line"! Hug a cop!
USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)