Anybody done one of these?

On previous dry suits it's been pretty easy: 20-30 little magnets, lay the neck
on a flat steel surface - like the hood of a car - mate the gasket and the neck
material using the magnets to hold them together with some Kotol/AquaSeal as
glue. 45 minutes max.

But the Kokatat has this outer collar around the base of the seal that seems to
prevent that.

I tried cutting a 3" strip from a 5-gallon poly bucket and then expanding that
inside the neck. But with the strip/neck material as taut as I could get it,
the gasket was still a pretty loose fit. Seems like the gasket needs to be a
snug fit to get a decent glue line. It also seems like, although the material
lays perfectly flat on a flat surface, it doesn't want to lay flat on a
cylindrical surface.

Can anybody offer up some advice? Besides FedEx or UPS...-)
--
PeteCresswell