Engineswap

"The 1UZ for the 30 and 31 are the same in every detail, apart from optional extra's.

The 32 has ONE difference and that is the oil pump.

However.

The 32 does have all the other stuff on it like the vane pump ( yes it is called the vane pump by toyota ) also the 32 has a front plate that enables the vane pump to fit to the block.

So you can put the 32 front plate on a 30 - 31 block and then you can fit the vane pump to the front plate, if you have a dead 32 engine you can take all the bits off of the 32 engine and fit these to the 30-31 block.

These bits include the longer bolts / studs to hold the front plate on, also the 32 has the double front crank pulley, you'll need that as well as the vane pump idle pulley and tensioner pulley.

So once you have swapped over all the 32 bits from the dead 32 engine to the 30-31 engine you are sorted.

Ah, the oil pump on the 30-31 protrudes with a lug to hold the alternator on, this has to go because the vane pump sits there on a 32, however you can cut this lug off as it is only alloy.

So, apart from the alternator lug, and the extended bolts for the front plate you should be ok to go.

The only other thing is the year of the car, post and pre late 93 have a different wiring loom, all 32's have TRC so they have the extra sub throttle gubbings for the TRC, most UZZ30 do not have TRC so they wont have this and that means swapping all that over including the wiring, and most, but not all UZZ31's have TRC so check before you put the engine in."

Source: http://www.soarerworld.com/forum/archive/index.php/t-32304.html