Petrol tanks

[achandler]

I have been advised by a couple of P2, P3 owners that the inside of the Petrol tank has a "tinned" coating and should not be grit blasted.
I am about to drop the tank out of my P3 to get it cleaned out, and the Company involved has said that if the top of the tank is just soldered on, as I believe it to be, then they will remove the top and grit blast it out, and then recoat, after checking for any pinholes or obvious damage.
Any comments or advise.

[Phil - Nottingham]

It is lead coated steel on P2 and P4's and early Series LR's. I cannot recall seeing nay "top" to unsolder - a side though could be reoved