Also note that 1500 trucks have a thinner frame than 8-lug trucks. Not a huge deal for a daily driver but you'll have to stick to the door panels tow ratings even with full 1-ton drivetrain.
Umm, the 454SS had five lugs.
I thought they shared the same frame with the regular 1500’s(?).
I believe the tow rating had to do with:
1-Engine torque
2-Drivetrain gearing
But who really gives a crap about tow ratings for a fun cruiser?
The guy wants to build a hot rod.
I thought that I read the small blocks used the same mounts as the big blocks - but I could be mistaken.
You could probably check replacement mounts on Rockauto to see is the V6 vs SB vs BB are in fact different.