It is a fine motor. Basically a low deck version of the factory 426 which was a very, very good motor design. Ford 427, Chevy 427 and the Mopar 426 are all classic 4.25 x 3.75 (or close enough) motors.

Only thing I'd suggest is to use the longer 440 connecting rod in order to give you a lighter piston. You'll still have plenty of piston height with the 3.75 stroke. If you're willing to spend a few more bucks then use an aftermarket 440 rod with a .990 pin and you'll shave even more weight from the rotating assembly.

Call Diamond Racing for the pistons. They build the 383 stroker piston on a regular basis even if it isn't a stocking part number.