sorry a bit late ..
After visiting René, as I was going through a full restauration, i.e in cabin "roof" was off. Well probably is good enough the take the "rim" carriing the internal light towards the engen bay off, I injected throught the gap as it appeared massive OVATROL, a semy hardening fluid for vintage car restauration..I mean massive..! I used a spray gun per kimk.
Matthias from Germany