So every o ring in the reg has been changed and it still leaks out of the hole?
Change that 008 once more, put some lube on the bottom stem of the piston and shove it in there to lube it.
I had constant problem with my reg, did all kinds a things according to Bates, and then it all just went away after changing an o ring that seemed perfectly fine that I had already changed.
Call Mr.Bates at PE and he WILL NOT sleep until your gun is working
At least it will seem like he's that concerned.