I know this is an old question but it's a good one. Lots of rear end choices for the B110 that can handle it. See our tech article Rear Axle Swaps. Perhaps the easiest are H165 from Datsun 1200 Truck or H190 from Datsun 320 truck (neither need narrowing). Nissan only used H165 or bigger behind the Z engines


Factory stock Z engines had balanced crank & rods and 3-angle valve job. The combo of 85mm bore Z20 with 89mm stroke Z24 crank results in 2020cc (compared to stock Z20 with 1952cc). So that's an increase of 66cc

factory ratings
* 89hp @ 5000 rpm Z20S (single carb)
* 99hp Z20E (EGI i.e. port EFI)
Since these are manufacturer ratings, they are net at the engine

I'd guess with the ported head, larger carbs, camshaft and exhaust headers it might make around 115 hp @ 6000 rpm and 101 ft. lbs. torque. The bolt-in H150 from 1975-1982 will handle that torque if you don't drag race it