Dis-assembly trouble

I went to disassemble my green laser. after unscrewing the protective cap, I went to pull out the diode assembly, only to pull out a brass ring that had been threaded to attach the cover. It does look like I could possibly push it out from the battery end. There is enough sticking out of the business end that I could grab with vise grips, but it also houses the IR filter.
It looks exactly like this one from Boblaser: BGP-007


Any suggestions?

Bob