2.4 Puma Cylinder head casting failed + MT82 gearbox q

The cylinder head above the exhaust manifold has failed. Unfortunately this is an oil galley and the entire contents of the sump sprayed out over the next 1000 metres before we parked. No warning lights came on, we just reached where we were going. Engine was cold so no smoke from oil hitting the exhaust.

The engine has done 150,000 miles so I'm thinking that just getting a lower mileage complete engine and fitting that might be the best solution rather than source a head, get everything transferred etc to a now unknown bottom end? I've not go the funds for one of the new engines and generally sceptical of recons.

The gearbox is getting noisy so could do with replacing too and this feels like a good opportunity. Is a 2.2 MT82 with bell housing a direct swap into a 2.4?

I am fairly sure the gear boxes are the same. There are differences between the 2.2 and 2.4 engines, for example;
different ECU programmes, some sensors different, different turbos and exhausts, different fuel pumps, different fuse boxes. Probably other differences too.