I can’t get a screenshot right now, but if you look at GB 2, at 33:57, you’ll see Egon putting on his proton pack in the courtroom. Inside the booster tube is the plug, but it looks reeeeally shallow. Most packs I’ve seen have the plug looking deeper. Does anybody know what’s going on there?
A couple seconds later, at 34:21, Peter’s looks hollow, but Ray’s in that scene also looks shallow like Egon’s. Hmmm… Anybody notice this before?
Shane
what you are are seeing is a difference between pack builds in both the original packs and the GB2 packs. some of the original GB1 packs had different heights for the booster plug, as did some in GB2. The packs that were built for GB2 have the booster tube and plug molded into the pack. Therefore the space around the tube as well as inside the tube around the booster plug is all filled in. In the courtroom scene, the packs worn by each actor vary from shot to shot. also if you pay attention, several times you will see ray wear the same pack egon was just wearing, or vice versa.
little interesting fact: the same hero pack was used for both actors in the part where venkman flips on his thrower and says “do” and egon flips his on and says “egon!”
Interesting! Well, this thread can close down now. Haha!
Thanks again, Kind! You’re a well of information! I think I’ll go the GB2 pack route and cut down the plug a little to make a filled in version. 
Shane