Thanks for the last PPM bettatail...
Here's what I just finished doing...I removed the relief valve and plugged the port using a 1/4" NPT plug...the same was done for the outlet port.
I connected the regulator to the co2 tank, opened the co2 release handle and now the HP gauge reads "800 psi" (I decided not to wait 6 hours to see if there was a pressure decrease on the HP gauge as I had already done this before and there was no change whatsoever.) So, I closed the co2 tank release handle and opened the regulator valve to charged the LPG to 100 psi, then closed the regulator valve (counter-clockwise) completely. Finally, I removed the regulator from the co2 tank. I waited 10 minutes and took a picture as shown below to record the reading on my LPG (95 psi).
It has been ~11 minutes and the new reading is 90 psi.
Finally, after a total of 6.5 hours the new reading is ~42psi.
At this point, I'm almost certain that there's an issue at the second stage of the regulator.
I will do a soapy water test on both plugs and the LPG...I even have an extra LPG that I can use to narrow the locations of a leak.
Let me know your thoughts.
BTW: I am only doing about 2-2.5 turns of yellow Teflon on the male threads...should I be doing more?