It's usually something pretty simple on a vauxhall of that generation to be fair as they were really well made cars in the 80's/90's.
Nothing like the rust issues of fords of that age either so don't get too concerned about that and all those problems listed above wouldn't cost £150 to fix if you did the lot.
Could pm chip as well as he's done a lot with these,particularly the c20Let motor.
I think the Saab motor almost fits in directly if theres a LET in it already and they start at about £200 second hand so even if the worst happens it's not too expensive!!!
Migwebs a good site as well,glad your enjoying it.