Nice one Lyle.
Another useful pointer for anyone reading this and considering buying a new suit...
I always try get a suit that is very tight...I can fit quite comfortably into a Mens Medium suit, but go for a Mens Small because it fits like a glove with very few loose bits. Fact is that the tighter your suit fits the warmer it will keep you and it helps prevent rashes forming behind your legs etc...
Obviously this is all within reason and you shoudl still be able to flex freely in your suit without it feeling like it's going to tear. Try standing upright and touching your toes. If the stretch is ok around the small of your back then your're good to go...if it's too tight buy a bigger suit and phat up until it fits
Good luck with the rash Super...vaseline does help