no pvc pipe needed, nothing is structural until you glass it
cardboard, even thin t-shirt material, will get rigid with a little resin on it
then you start glassing. i rarely mixed over 6oz of resin at a time
flat curves i'd use 4x4 pieces of 3/4oz mat, tighter curves get smaller pieces
use mdf for mounting things, ac vents, cup holders, radio, switches, speakers, etc...
as you see, i went with body/dash color, i started out just hiding the vintage air unit
you can see some of the brackets i started with welded under the dash
the original console was bent sheetmetal, then i found fiberglassforums.com
