Might want to go over to JoeCustoms and ask them in the http://www.joecustoms.com/forums/viewforum.php?f=15 section... or you might even find your answer there.... there's a few people there that are building their own vehicles from styrene ..
for example ... http://www.joecustoms.com/forums/vi...hp?f=14&t=36924

might even read http://www.joecustoms.com/forums/vi...hp?f=15&t=37834