I'm in the process of rebuilding mine at the moment and its a bit of pain and not too pretty (not a problem as noone can see it!) So I agree fibreglass ones would be a well worthwhile addition.
I would imagine it would be quite straightforward to make in fibreglass, the only problem would be the two mounting brackets on the sides being able to support the heater matrix itself (when its full of water)
Rupert
"With great cars comes great responsibility"
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