Hi Chris,
I'm familiar with feeling uneasy about taking on the role of QC/QA Manager. I had to do that very thing several years ago when our QC guy became very ill and later passed away before I was able to get the info and experience needed for the position. It is a big role to have to step into.
I'm not that familiar however with ASME sections or code, but several forum users are and are eager to help in anyway they can, so ask questions and bounce things off of them that you are unsure about. This forum has a host of knowledgable people that monitor the posts pretty regular and answers usually come relatively quick.
Good Luck with your searches,
John Wright