The Allen bolt for the PGO likely has blue loctite. It may help to get the wrench in good deep and square and tap it in the CC direction to free the bond.
When you reinstall it, add a washer to assure that you do not get it in too far to affect the action...
When you say you cleaned it, did you do a thorough strip and deep cleaning? Bronze brush to the bore and chamber?
Have you got it back together?
The above is the video I refer to and refer others to.
Thanks for all the help--I'm in a better position than I was yesterday. So to answer some question the gun is reassembled via the slight disassembly it went through (not even field stripped just removed the barrel and the pin to hold the trigger). I want to completely field strip the gun and check all the parts etc. Clean them thoroughly and make sure all parts are in moving order so to speak. I still CANNOT get the pistol grip off, why I don't know. It's on their ridiculously tight I've even tried using some Remington gun oil etc. No luck yet.
AS FAR AS THE AMMO I was using; Yes, it was cheap they are called Estate Loads. Tiny Bird Shot loads 2.75 inch small, light load ammo. Any ideas on removing that bolt would be loved at this point lol.