I can also attest to the nastiness of the insulation. Even on my nearly rust free bus there was mold in the insulation especially under the windows where condensation runs down the panels.
As an interesting note, Carpenter only insulated every other opening. The one ceiling panel we removed so far was about 20"x 6' even though the cavity is about 31"x8'. Don't bother with all of the work to build a bus if you aren't willing to remove the panels. At least do the sides, the roof could theoretically be left alone, but why not do it while in demolition phase?
At least on our bus drilling the rivets is no big deal. I did the one side, 15 feet, in about 30 minutes or so. I have read that carpenter did some shoddy riveting but most that I have seen are fine. I used bits that are bigger than the head as well as smaller ones that are just right to make the rivet shank disappear when drilled. With the big bit you have to deal with the shank left in the hole. Ill just use a cut off wheel on those. I don't really understand all the talk of air chisels and destroyed panels, we could reuse my roof panel without even paining it if we wanted to. I have noticed that my bus has far less rivets than some brands so that makes it easier.
I say don't debate this as it is very important to have a solid base to start with, just get it apart and I believe that you will end up saving time in the end as it will be far easier to build out without metal in your way.
