marauder field and target regulator

The regulator in my Marauder F&T failed (leaked) last year and Crosman sent a replacement. The new regulator is not as consistent as the original so I'd like to repair the old one and use it. I can see that the internal o-ring was badly stretched and deformed so I assume that the leak is from there. Unfortunately, some of the washers fell out and I don't know what order they should be in. I am trying to take apart the new regulator to check the order, but the plastic endcap adjuster is glued and I can't get it off. Does anyone know in what order the washers should be in or how to remove the glued endcap on the new regulator?
 
i just thought of something . what if you remove the guts from your reg so its a shell to increase plenum , then remove the o ring on the air tank side of the gage block so you can get a huma reg to set on top of the whole thing and by removing the o ring it should let the reg vent to the atmosphere , i do own the same gun but was early in messing with guns that i never thought of this , i think it will work , then your gage will show reg pressure and you can get a huma fill valve if you wish to have a gage for the tank pressure , i personally only have a plenum " reg" gage and an fine with that . and with so much plenum you can go to a better valve and light JSAR hammer and light hammer spring if you want a gun you can adjust for alot of different tunes , just a thought , i think it will work and at least get you out of your crossman reg and into a world class reg