disco engine change

new to the forum, and hoping to get some useful information from the forum.
got an m reg auto disco tdi which keeps blowing head gaskets and a h reg manual disco tdi which has rotted out but the engine is good so will the manual engine and auto transmission match up or are there diferences in bellhousings or cranks and such like?

john

oops, thought I was in the disco list-feel free to move it if it needs to be

Is the m reg a 200tdi or 300 tdi

I couldnt say, how do you tell?

You will know as both engines look different. Mainly the Turbo

M reg will be a 300

That's what I thought. I'm not sure if 200tdi will go with a 300tdi auto box. but matching engines should be ok.