Use 2000 Chev S-10 4X4 front wheel bearings. Install these in the rear of the chassis.
This will give you the correct bolt pattern too.
If you are building your own hub bearing support/upright you can find this info on kitcentral.
The caliper will fit nice once you install the bearing and rotor. You will only need to weld on a modified piece of thick angle iron, about 1.5"X1.5" to mount the caliper.

I modified a rear caliper from a Nissan 240 to make my emergency brake.