I've basically got a GSI head because it was already on the engine when i bought it just over a year ago. I think i said this before but it has the best design for air flow etc.. out of the 1600 Vaux's, which ultimately leads to more power.
My engine was originally in a Nova, hence why i have a SV block and SE head. The SE block "went" incase your interested.
Here's a few pics I've taken over the year i've had it.
If ya cambelt teeth look like mine you should be OK.
Also I don't think you'll need to change the camshaft drive, unless it looks like mine, because the Nova and astra's had the same one. Mine is actually a 1300 drive as this was what my car originally was and it was easier to keep the existing one than try and fit in a new loom etc.. for the 1600 ignition.
Also the camshaft housing, recognise it as one for a mechanical fuel pump? All you need to do for this, unless you're going to have a mechanical pump, is just blank it off.
The Jetronic 1.6 engine's distributor uses a funny pin type drive on the end of the cam. The Delco one above uses a slotted end on the cam.
If you had to blank off the mechanical fuel pump mounting on the cam carrier then that isn't a GTE. They aren't machined out on GTE's, the mounting holes are still there for the aux air valve.
Anyway, You could keep your cam carrier, dizzy and bits and plonk a GTE head alone in there. Change your cam followers over to the GTE head though (and keep them in order) as they will have worn to the cam lobes.