Thinking about it we've had the tranny 10 years and a Sierra and Mondeo before that. So some while since we spent £1,600 on a chocolate cam from VW Heritage. They accused us of not changing the oil!
The one we have now is 2.1 Auto. You need the bigger engine with an auto box.
Not sure what it is about the heads, but VW Heritage fit new ones, or did on ours.
We had problems assembling the two halves, tricky job, feel we got a main bearing wrong.
Would say its very difficult to assemble on your own if not impossible.
But as you say worth a try to you.
Be sure to keep the joints clean and use correct sealant, or similar, VW stuff is not cheap, think we used Wynns at the time.