Does anyone use this?
It is highly desirable to prevent the ingress of TKS fluid into the belly cavities.
The firm known for the old PR1422 etc (a highly effective 2-pack adhesive-sealant – example) makes such but nobody in Europe stocks it, and – like all the good stuff – it is “hazardous goods” for shipping, or there is a ridiculous MOQ 
What about just gap sealing with 3M tape?
It needs to come off years later with zero residue. I’ve never known a tape which can do that. And it must not pull off paint.
So you need an access panel sealant such as PR1428. Here is one in the UK.
Thanks – that looks just the stuff.
That Ebay link is expired stock from 2020 but for this application should be fine. I bought some and will test it. There is a special way to use just a part of a semkit
I’ve been using PR1428 for years on fuel tank access panels with success. It is similar to 1422 but with lower adhesion hence easier to remove without causing damage, but still labor-intensive.
If expired, depending on storage temperature, it may not cure to the proper hardness.
I would prefer some form of soft gasket in material if needing to remove panels as often as yearly.
