matt,
glad to see you are here.
the 250 and the 292 are good candidates. both can use simular parts to turbo them.
the 250 wil be a choice if you want to rev the engine freely to 5-6K rpm, the 292 will gain cubes but also limit easy reving rpms. i like the 292. torq is king for the street.
what chassis are you putting this into? i offer a nice cast turbo manifold made to bolt on either the 250 or 292. pm me for details.
you will need more specs for the turbos you have to know if they will work for either motor.
be sure to search the power adder forum and you will find plenty of turbo related posts. tom