A few years back we had the NE Kokatat rep to our CT club for a seal changing demo. He recommended stretching the seal over a large jug before resorting to trimming. I wear a 16 1/2 shirt neck and always stretched mine and it was fine. Knowing you, you're and ex large suit. Better larger than too tight. Baggy is good. I use an ex-large because I'm 6'2" tall not for width.

Kokatat's web site says to trim seals. We've been bugging Kokatat to start using ex-large seals. Why should everyone have to trim a seal on a new suit? The problem is this. In three years your neck seal will loosen up substantially. It just the nature of latex rubber. The reason they use rubber and not silicone is because silicone would not go over your head and resume it's original shape. Unfortunately, it's still the best thing for water integrity.

Kokatat has no ex-large seals-only large. Many of replace our neck seals when they go with an ex-large from dive shops.

One last thing: make sure you neck seal has not curled over itself on top and you have a double thickness of rubber squeezing you. Rob, I would stretch it over a gallon milk jug for weeks in the beginning. You may not have to trim it. If you trim it and do a crummy job and have nicks, it can go prematurely.