POR15 removal

I'm about to seal my Norton fiberglass race tank for the 3rd time. The first 2 times it was done with POR15.
The POR 15 didn't fail, the bike was dropped & ruptured the lining both times.
I've been told to use Caswell this time.
The information on the Caswell web page states that the original POR15 needs to be removed with paint thinners containing Methylene Chloride.
I have used this with dry wall screws & nuts to help loosen & remove the POR15.
I lot of goop came out but I'm unable to verify the removal in the deep dark corners where I can't see.
I'm worried that there is still some soft goop in these corners & it will effect a good seal with the new Caswell to the fiberglass.
I'm also worried about using more paint thinners that might eat away the resin of the fiberglass. The rest of the inside of the tank looks relatively clear of POR15.
Is there some solvent I can use to wash the inside of the tank out to make sure all the soft goop is out?
Thanks

pouchy750 said:

I'm about to seal my Norton fiberglass race tank for the 3rd time.

Click to expand...

In this case I'd rather use the existing tank as a pattern to make a mould set and laminate a new one.


Tim

If the POR didn't fail, why the insistence on changing brands?

If you aren't totally sure you've removed all remnants of POR, and you don't want to do more internal cleaning through fear of damaging the tank, and you worry that any un-removed POR will effect the Caswell product...

... then surely, the easiest thing to do is leave the tank to cure / drying thoroughly inside and simply re-coat with POR ?!

Also, if this is a race bike, don't forget that (most?) race fuel and avgas is ethical free. Currently at least.