No secret I am not a silicone fan, but I have not tried some of the new stuff. I will say that I do not like Right Stuff. IMHO it's messy glue that often has internal bubbles.
The thing that gets me is "too much space" I have never had that issue. Especially with something like a Felpro end seal and an RPM, in fact, every RPM intake I have has needed to be trimmed and I even mix and match cork gaskets to get the crush I want.
I am not sure what you are using, Mr Gasket gaskets are nice, but I toss their end seals usually. More often than not, the issue is not enough space after a cut deck and heads.
I'd look close for the cause, now, if the ports line up and the angles to the head look correct, head gasket tabs aren't hanging the intake, certainly cannot argue that the end rail cork won't work, they need to be compressed, but I just haven't see that
As far as time to fit, it's all a trade, time to fit, or time to dry, depends on your schedule, neither way is a free ride.