I received the tank sealant and sealant gun so I could experiment with the “goop”.
Also I looked at the fit of the fuel cap and drain valve.
I’m using Flamemaster CS3204 Semkit. You can mix this by hand or with a special expensive mixer. I ordered an accu drill adapter but you have to be carefull to mix slowly; 50 strokes and one 90 degrees rotation on the push and another 90 degrees on the pull.
More info from another vendor: How to Mix an Injection Style Semkit® by Hand
I’m going to use Acetone for cleaning the aluminium and rivets and not MEK or Methyleen Chloride.
This is the sealant gun I’m using: Sealant Gun Combo
One thing I noted is that the sealed rivet do not expand that much as the Polygrip rivets, so hole size is much more critical with these rivets!
I also did a test fit of the fuel cap:
The 2 rings go on the inside. I don’t need to chamfer the ring for the fuel cap because it’s already flush with the skin out of the box, maybe only a bit depending on how much sealant goes in.