[cscobra]

Your plan (moderate 428, WR, small in and small out, 3.31 rear) should work just fine. I'd go with ERA's recommendations regarding tailshaft and driveshaft lengths--they've had many years of experience to perfect these designs and they know what works. Your proposed combination should be great for reliability and durability, and you'll still have more power than you'll ever consistently use for the street.

By the way, my rebuilt toploader came from GT Performance Ford in Penn Yan, NY. (GT in this case stands for Gary Tyler). I learned about GTPF from ERA.