With regards to the current chassis, I am thinking something along the lines of either a fiberglass patch, or perhaps Selleys Knead it steel putty. Have you used any of these in the past?
Thanks
regards
Tyler
I used a square of tin glued inside a Mustang GTS with liquid nails to use as a bridge, then Selleys knead it on top. I think NormK's suggestion with the fibre glass backing is better with the intricate moulding around the hole on your base. I would hunt down another base myself an dice that one. Victa would have made literally thousands and they can still be obtained on the cheap. I was given two in the last year!!