got 2 H's different trim levels looking to swap between them

Hi all,
I picked up 2 problem child's cheap (we cheap for here in Aus)
150 pound H estate CD trim level Z18xer my07.5
250 pound H 3 door SRI my07.5 z22yh

Need to Make the Estate my keeper and might send the 3 door to the breakers or swap the estate stuff back into it and sell cheap

I only bought the 3 door for the front seats and wheels as the estates seats are trashed and it only has steel wheels.

The Estate has a blown head-gasket as water in oil. it barely ran when i picked it up. Every error code known to man.
A map sensor and new coil pack fixed that. Still throws misfire on 3 and can be hard to start if you run it then tray and start it again within about a day. Thinking the water is leaking into 3.
If i do the head gasket i will do the oil cooler and timing belt I have already done the waterpump.

The z22yh has a blown high pressure fuel pump but besides that the car has been well looked after I was offered the 3 door by a mate it was his daughters she has a company supplied car and didnt want to spend the 800 Pounds a high pressure pump costs down here.
Wondering if it would be worth doing an engine swap rather than fix the Z18xer is the wiring much different, would mounts need to be changed, Take it I would have to change the BCM dose that create any other problems as the estate doesn't have climate control and only has the basic Dash.

It will only be a daily and mostly be driven by the wife hence needing the estate over the 3 door.

If i don't do the engine swap any other things you guys would recommend changing other than the seats and wheels.

I haven't picked up the 3door yet and haven't really seen it in a long time as it is up at my mates farm about 200 km away


Thanks
Jason