I'm curious, is the collar and chamber cap much different from the v1 to the v2?
My retrofit v1 with v2 base works fine, the collar is a little tight but works fine.
I couldn't imagine the v2 collar and chamber cap making much (if any) difference?
The difference, when properly done, lies with the way the cap fits onto the sleeve.
The area on the sleeve where the o-ring of the cap seals against is greater in depth making it so the cap can be screwed on all the way or only part way to adjust the length of the wick holes and still maintain the seal. They should interchange just fine except for that.