In August of 2019, I decided to carry out some long term experiments to solve the issues with my MkII's opaque headlight lenses.
https://the75andztclub.co.uk/forum/s...highlight=lens
To test my theory I scrounged a gash Mk I lens from a local member. Idea was to try ordinary clear coat lacquer on on of the lenses on my Mk II and on the donated MK I lens, the latter being left out in the full sun and weather for a test period to see what developed. My Mk II spends much of its time in my garage, so hardly a fair test of deterioration.
I began by thoroughly abrading both headlights down to bare polycarbonate, with course wet and dry, until I was certain all the original coating was gone, then polished them back up, with finer and finer grades of wet and dry, finishing off with a metal polish, before washing thoroughly.
That, I followed with several coats of my clear coat aerosol. My finish proved a little disappointing, in that marks in the form of what looked like cracks appeared in the coating on both lenses.
I managed to polish the worst of the lines out, before finishing with metal polish. Too the good - neither lens has shown any deterioration at all in the 6 months since I did them.
When I have simply polished them up without any coating, the have deteriorated almost before my eyes in just weeks - so I'm that a successful experiment.