2 golfs and a polo- big block to small block

Ok guys ill fill you in with what we've got:

Sammy Summo Mk1 been converted running a 1.8 carb engine out a rocco gt2( used to be a small block mk1)- Project

Mickey Mk1 Series one small light model with a seized 1.1 rusted beyond saving - Donnar
Pete Polo mk3 coupe( non GT)with a 65k 1272cc 5 speeder set up for it, new clutch and few other bits just needs the head gasket done.- donnar

Now the plan is to take out the 1.8 8v out of sammy and put in the  1.3 engine out of the polo donnar car, reason is we dont like the current 1.8 or  the wiring( we  baught it after the firstl swap). Reason we have  the mickey the mk1 is for all the wee bolts and clips etc needed when re building a car. So…what do wee need to keep in the project car(sammy) what do wee need to take from the small block donnar mk1(mickey) and what bits do wee need from the polo?

My worries are:

steering rack
wiring
engine mounts
Manifolds
Drive shafts

I bet there is lots more wee need to concider so any any help will be great guys thanks.

Ill just add that we are pretty new to this sort of thing and inteand to do all the work including the re spray ourselfs.

Paddy