Roll Bar Bolts

[Tatey]

I'll be welding the ones for the roll bar mount and the seatbelt anchors, it says to do it in the book, and i'm guessing its because it would be a right bitch taking the roll bar off and having to get a socket in there when the shock and all of the bodywork is in place.

You bother because your a kind fellow and it is much appreciated

Another question, when nuts are referred to as A2 or A4, is this the grade of stainless steel used?

Finally what is the difference between type p and type t nuts?