Best Slant 6 Reference Manual

I'd love to tear mine apart in the swinger and build it up nicely with some performance goodies but it runs too darn nice to even want to mess with it, but when the time comes, I will also add a three speed to the floor since it's already a three on the tree column shift.

Doesn't Mopar Performance have how to build slant six engine books?

Yes, but it's not a very good one. There are all sorts of bizarre errors in it - the book confuses some doctored "official" specs for NHRA stock class rules with the real production specs in several places, it claims the Lean Burn ignition used breaker points, and they often didn't check if particular performance parts were still being made before they printed the book. Plus, they often neglect good performance parts from non-MP sources. In essence, the book is intended as an advertisement for Mopar Performance parts.