All VW four cylinder water cooled engines, from a 1975 era 1.5 L gas through the newest 2.0L PD diesel have the same trans bolt pattern, so the trans should bolt up no problem.
As far as I know the 1Z and the AHU long blocks are the same, so the heads or blocks should interchange either way.
The only difference I am aware of between the two engines was the turbo charger. 1Z usually was supplied with a Garrett GT15 turbo, the AHU had a KKK03 turbo.
Piper106