I've printed MileyORiley's Proton Pack and am working on finishing it at the moment. It's an awesome design and is slightly reduced in size (it's 90% scale) which is perfect for me as I'm quite short.
This Thing goes with this design - https://www.thingiverse.com/thing:2479141
I remixed the Booster Tube to add the recess that was missing from the original as personally I felt that it needed to be there to satisfy my OCD. I did a few variants with different sized centre parts but this one seemed close-ish to pictures from the movie. I did look at a few plans but I decided to eyeball it.
This could probably be printed with less infill, I just happened to do this at 20% so feel free to experiment.