Looks like a pretty regular mud bogging set-up...just about every competitive bogger out there runs miss-matched tire/gear set-ups , front to rear.
I have a buddy that use to campaigns one fastest mud/sand diggers in the country and ran a Dana 44 ... Yukon shafts joints and a spool ... nothing special.
I couldn't believe a 44 lived up front.. funny thing is he was considering swapping it out for a Dana 30 for weight savings..
His rig ran an all Alu. blown Keith Black on alcohol and made like 2400 hp.