Case W24C loader with a 5.9 cummins repower

I have a Case W24C I would like to repower with a 5.9 Cummins, I have the engine with a sae 3 bellhousing, I think the trans is a Allison tt2421-1, anybody know what flywheel I need on the cummins? the cummins was in a repowered Clark 55C that had a 6 cylinder Cummins, It looked like the flywheel was going to bolt rite up but the clark flexplate measured 13-1/2 from center of bolt hole strait across to bolt hole, the allison is 13 center to center, do I need a different flexplate or flywheel? or it this going to have to be a custom deal? Thanks, Mike