I have used the VHB tape for everything so far but it must be 3 years old now and I’ve heard it has an expiry date - so I might try the Proseal method.
I assume you basically scrape almost all of it off? How do you ensure that it doesn’t build up in the countersinks and hold the skin away from the trailing edge piece? I riveted my tanks wet for this reason - could never believe that a clecod part would be as tight as a riveted one and couldn’t get my head around how the Proseal in the dimples wouldn’t hold the parts away from each other. Or do you clean out the countersinks of proseal somehow? (Difficult since the part is tiny and would have Proseal on both sides.)
Having said all that, apparently the adhesive isn’t structural, so maybe the tape would be fine.
https://vansairforce.net/community/showpost.php?p=1424922&postcount=7