Matty,
I'll reply this time instead of winding up with a seperate post!
I'm doing much the same, but I've only just started collecting the bits, here's the anecdotal research to this point in time...
1st way is to rig a cable, a la CB performance. Looks ugly but works.
If you search the web or thesamba classifieds you'll see the mechanical linkage used that retains the stock cable.
The manifold is quite tall, and has two lugs cast into it on the LHS runner (as you look at the engine). A rod runs through with some arms 'n' joints.
Trawl the web and you'll see.
http://www.empius.com and you get a decent enough picture of their single HPMX (weber clone) setup.
Unless you live in QLD or some other warm climate, you need a decent manifold with preheat that runs all the way up to near the carby base.
HTH
Ctefeh