Well i can't say for sure yet, but it doesn't look to be bigger then a regular 510 atty. If it is, though, I'll just put it in a drill press and sand down the outer diameter till it fits. I'm pretty determined to make it work somehow.
Adapters do fit, CJ. Here's the problem though :

That's with the cap completely open. Barely, and I mean barely, touching the bottom o-ring seal. As you close, it exposes that 510 adapter even more. You could try dremel, at least, half of the 510 adaptor, which in turn might leave you with lesser threads for the rba. As your turn your rba for whatever reason, you might lose the connection with the adaptor.
Nic