Has anyone replaced a 280GE M110 994 engine/trans with a 280E sedan M110 (JDM)?

My 1982 RHD UK Spec 280GE LWB threw a rod in the middle of high season on the farm (I was collecting seventeen 1.8m²  panes of glass for the greenhouse that we need for autumn starts - must be commissioned by the end of the month - worst time possible for the G wagon to stop running).

On our auction site, TradeMe, I found a 1982 Japan Spec 280E sedan (oddly LHD) with documented 64,000 km, so rather than rebuild my M110, I'm doing a long-block swap so we can get it back into service ASAP. The truck repair shop that sold me the sedan is happy to do the hard work, but they have never touched a G-wagon before, so I am on point to tell him what needs to be done... and to know what gaskets to order since parts to NZ can take ten days to two months.

Has anyone done a sedan to G wagon swap, and if so, what needs to be changed over? I know the oil sump, exhaust manifolds, and I will be swapping over the whole K-jetronic system because I just refurbished it with new parts.

Also, will the sedan transmission fit in (yes I know I will lose the super low first gear ratio, but as a farm truck, the G-wagon is long past its overland endurance days, The current transmission has 405,000 miles on it. The replacement is 38,000 miles, but unless it is easy, I won't bother. If it is a direct swapover, I would love to hear.