Here's a few photos with some pretty basic but important tips when doing something like this. First off, use a razor saw with a miter whenever you can and be sure to sand off the burs before replacing the stock back in the miter for the next cut. If you don't, there's a decent chance that the material will lift a bit at the burr causing your cut to be less than perpendicular. At least for this project, everything needed to be consistent and accurate.
|See what I'm talking about. This makes a big difference when you're working at milometers.|
Once all the vector thrusters were cut...
...it was time to mark off and cut the intakes. This didn't take all that long but I did cut extras just in case.
Now that the main form of the Jump Pack was coming together, I went in to some details like the exhaust nozzels shown above and the bit of shielding shown below. Here's another tip: layout the bits you need to cut so that the cuts can be repeated comfortably and consistently. Here I laid out the shielding so that the last cut would be the one that frees all the pieces at once.
These next two shots show the models with their packs. If you click the images, they'll open up a larger version for better viewing. You'll notice several other steps that went into rounding out the effect but I figure these are self explanatory. The main tip here is to make sure that whatever conversion you plan to do on a multi-model scale, you should make sure it's easily repeatable which also means making sure you can gather all the elements you used the first time around.
Of course, I did paint these but figure I'll let you see the final results when I post the display board I'm making for the army.