I just renovated our 30' boat. I have recently done everything you need to now do. I used a great product for filler, DO NOT USE WEST! It is expensive and a pain. I will go out and find my stuff and post the brand on here. It's a two part epoxy
filler that works great and goes a long way.
I dried the blisters on ours out w/ a heat lamp and some days of time. I had four large blisters to deal with.
Use Interlux 2000 epoxy
barrier coat and I will post the brand of the filler shortly. Any questions just PM me here.