Here are instructions on how to clean up a Vaccumformed proton pack.
Supplies:
Razor Knife
Bondo Auto Body Filler
Bondo Glazing Putty (For the pin holes/cracks bondo can’t get)
Course Sand Paper
Fine Sand Paper
Reinforcement Tape (tape with a bunch of square holes in it)
Extra Styrene Plastic (you can use the pieces you trim off the bottom)
Do these steps in this order:
1: Trimming Part A:
Use a Dremel tool with the widest cut off wheel you have (1" works best). Use Stefan/Bugstomper’s plans to find out the deminsions the Spacer and Upper Module should be. Mark a line all the way around for you to follow. If you use a Dremel, put it in a vice and use a level to make sure it is setup straight. With this method you simply find the right height and keep spinning the Spacer/Uppermodule arround until it is all cut off.
If you do not own a Dremel, you can use a pair of tin snips. Draw your line completely around and just slowly trim the plastic off by hand.
Trimming Part B:
Use a NEW razor blade. The sharper, the better. Simply shave off each piece of webbing layer by layer until you have completely removed it. Now, you will have some skinny long holes, and some short fat holes in your vaccumform. DON’T WORRY! Bondo fixes everything! 
2: Reinforcing the Upper Module:
Taking pieces of Styrene plastic, cut them to the lengths of the various flat pieces inside the upper module. Use Super Glue to put them in place, it bonds them together pernamently. Also, if you are using the same Styrene that Java does, Hot Melt at its highest temp. will work well to as it heats the plastics and bonds them together (duh, they are THERMOPLASTICS!).
Reinforce all of the corners of the Upper Module with bondo, this will keep them from flexing too much.
3: Apply your reinforcement tape to the INSIDE of the upper module covering the holes from where you trimmed the webbing off. Apply this stuff pretty generously. After it is set in place, take a slight bit of super glue and go around the edges of the tape (not the edges of the holes) to make it stay there pernamently.
4: Apply Bondo to the OUTSIDE of the Upper Module filling in the holes. Try to avoid applying too much as it can be a pain to sand down sometimes. Let the Bondo sit for about an hour before sanding it down and getting everything smoothed up.
WARNING: BONDO CONTAINS FIBERGLASS! WHERE PROPPER SAFETY EQUIPMENT WHEN MIXING AND SANDING!!! READ CAN FOR MORE DETAILS!
After you’ve sanded down your Bondo, you’ll notice some pin holes and such from where air bubbles were created. Fill these in by applying a LIGHT layer of Bondo Glazing Putty.
I think that is about it for the clean up proccess. You don’t really need to reinforce the spacer too much. You might want to do a little expandable foam, but that is up to you.
Any questions class?