I could be wrong, but I believe Joe runs the Boss RV-5 Reverb Pedal through the effects loop of his Carol-Ann (or Van Weelden, depending on his mood). It sounds like he uses a pretty substantial amount of reverb, just check out his videos on youtube. The reverb is almost unnoticable until he stops playing and then it tails off nicely. He use to use Fender Reverb tanks but due to reliability issues he switched to the more convenient digital alternative. I personally use a EH Holy Grail and it sounds just like the verb in my twin which is so overpowering at times! Great pedal, very authentic sounding without a lot of bells and whistles. See the thread dedicated to Joe's stereo reverb/delay and he explains it all except for settings. Just experiment and good luck!
'67 and '74 Fender Twin Reverbs, '74 Marshall 1987 lead mkII, Metro Superlead 100. Pedals from TC Electronic, Ibanez, Dunlop, BK Butler, Electro-Harmonix, Fulltone, Maestro/Gibson, Loopmaster switching, VoodooLab, Boss. Gibson and Fender guitars, Dimarzio pickups.