I think you need a narrowed rear end and tubs for about half of the tire width. At 8'3", you're nearly at the legal width limit of 8'6", and I think some states still have a 8' limit on some roads, so you'll be 3" over on those.
A few updates. Picked up a 383 Stroker small block. This motor pushed a '85 Monte to 12.5 in the quarter so it should be way more than my little car needs.
Chassis boxed