Thanks, I know of and rate highly Waxoyl. Like you I have/had older cars (Series 1 Land Rover, etc) and treated them with it.
Last week I took my now 6 month old Ocean to a Waxoyl installer in Norwich, for an underside ‘ramp’ inspection. I was pretty surprised at the (admittedly surface only) amount of visible rust. I have booked it in for 15 June for treatment.
I was planning to take some photos and report on how I felt it went, afterwards, in a posting. I did not find it easy to find what appears to be the right person for this job.
... then today I discover roof rust:
Yes still on seal #4 I had one seal fail in exactly the same spot as in your photo that is classic rust in the seal, get it cleaned off ASAP, look at the seal recess in the corresponding spot where the rust has transferred to the roof. dry the seal fully (leave it off until the seal is fully...
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