I couldn't find turbo v6 full floating pistons that don't cost less than full custom pistons to get exactly what you need would, can you post a link to the pistons you're referring too? These for example; https://www.summitracing.com/parts/jep-131556-6/make/buick The compression distance of 1.850" would even work with a 6.00" rod and the 3.400" stroke with a sbb 300 block. If the deck is blueprinted the piston would be .007" out of the hole(piston could be easily milled down that much). But seeing how factory blocks are usually taller than advertised, there is probably enough extra deck height to have the deck milled and have the pistons still .005" in the hole if that's where someone wants them. These pistons would be nice to use but after adding 2 more pistons would be over $800 for a set of 8, for a little bit more a full custom can be bought. And if you are saying you would adjust the rod center to center distance, there is only around a .012" difference between the sbc pin size on that rod to the sbb pin size. That would only leave around .005 to move the centerline to get a full cleanup which wouldn't be worth the extra machining cost to have done or the extra headache to do yourself. Are you looking into building a sbb 300 and the TA Rover heads? Also remember there isn't a good flowing aftermarket intake made for this combo so it would be limited with a factory intake unless you make or have a custom one made.