Cool thread! I actually have used the same stuff as body filler when rebuilding my cabs - Plastic Padding chemical metal bought at Clas Ohlson. It is toxic as hell though, and it gives off heavy fumes that will shorten your life by a couple of years. In one of the videos by Ully he uses something called Ponal Duo. I think I will order some from Germany and try it out. Apparently it smells like bubble gum.
By the way, before you lash out 3000,- SEK on woodgrain vinyl from Escapepod. I ordered the following for my Tempest, and it is a very close match to the original:
http://www.ebay.com/itm/161235122498?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AITAnd at a tenth of the price.
Apart from woodwork, recapping is the most tedious part of this hobby. I wish I could sit in on one of your beer and cap evenings. Looks fun!
Cheers!