It looks like I can use rods for a flathead Ford 85 HP V8 and pistons for a Japanese Diesel in a 216, and end up with a 250+ cubic inch engine with a major reduction in rotating and reciprocating weight, plus having smaller rod and main bearings. The same basic concept can be applied to 235 and 261 engines, with displacement of approximately 270 and 290+ cubic inches. There's also a custom length H beam rod for a Chevy big block V8 that has some possibilities, especially in the 261 block.
Jerry