I've been slowly building my Daimyo Boba Fett as well for the past year.
The gauntlet connectors I found a way to make them resistant to stress and semi-accurate. There are the connector STLs and I had to edit them to use aluminum pipes to go through them. I will post the link here later on and the diameter of the hoses (plus links), since I went through three different hoses and the last one seems to be the better look and diameter.
The size of the back plate (which has to be able to connect to the jetpack) has to match the collar armor. I know, it's a tricky thing.
Now a question for you... is your pack side lights (the blue LED), is it intermittently switching from blue to red?