How thick is the angled bit on the base?  Or am I better off making it as thick as the un-angled pieces? Thanks.

Parker, check out this thread: http://tardisbuilders.com/index.php?topic=4234.0. It has photos of the early (Series 1?) TARDIS plans that are posted at the DWE. Also, check out this post from DoctorWho8: http://tardisbuilders.com/index.php?topic=4414.msg53014#msg53014. It has a link to his outstanding downloadable PDF drawings (with measurements in inches) of the Series 1-4 TARDIS - the version with the panels that don't look as "square" as those in the DWE plans.

I hope this helps.

Dino.