I'm in the process of building up a couple of early Chevy spray-oilers, a 216 and a 235, with a pressurized crankshaft and connecting rods for a later model 235. It's necessary to tinker with the thrust surfaces on the #3 main bearing since the spray-oiler crankshaft has a wider thrust. Either widen the flanges on the crankshaft or narrow the main bearing web in the block- - - -either way works. The 216 can be bored 60 over to accept standard bore 325 pistons, making the "216" a 235, or it can be run with the original cast iron pistons to become a "224" with 292 Chevy connecting rods. None of the above is a bolt-in swap, but no exotic high dollar parts are needed.

There's even a way to increase the stroke on the 216 and make it a 258 cubic inch engine that looks "bone stock" from the outside. That involves using H-beam connecting rods for a Nisssan 4 cylinder, and aluminum pistons for a Buick/Olds 215 V8. Similar mods to a 235 turn it into a 270, and a 261 with the stroker crank approaches 300 cubic inches. "All of the above" can be done without altering the stock appearance of those engines.
Jerry