I've been working a dash for the Series II for a couple of weeks now. It had three chunks of missing material round the mounting holes for the lower trim piece, plus a thin crack from one hole up towards the hole for the fuel gauge.
I used a two-part epoxy resin from JB Weld and it seems to have worked really well. I used it to completely fill in the missing material around the mounting holes. For the thin crack, I used the Dremmel tool to cut a u-shaped channel the length of the crack on both sides of the dash, then filled the channels with the JB Weld.
The stuff cured nicely, and sanded really smooth.
As an adhesion test, I smeared a dab of it on to a sound portion of the dash, and after it cured I was not able to chip or pry it off--it had to be sanded off.
Of course, time will tell, and it shouldn't take too long, as we intend to start autocrossing the car real soon now.
Anybody else have any experience with JB Weld in this sort of situation?
Ramon