ive looked at that boxcab before it was nice, but, man the price tag! ill build one my self for that price!
altho the box cab is fairly light i belive there might be a soloution to your problem there.
The Home of Articulated Ugliness
It looks like a lot of fun if you have the room for the track. Warren Mumpower over on large scale central built himself a box cab and flat car to ride on. He has a friend with a track. I'm sure he could help you out.
http://www.largescalecentral.com/LSCForums/viewtopic.php?id=7743
http://www.largescalecentral.com/LSCForums/viewtopic.php?id=7258
makers of the kits he used -
http://www.plumcovestudios.com/
-Brian
Get the Garden Railways newsletter delivered to your inbox twice a month