NHRA Welding rules??

the no grind is in reference to trying to pretty up the weld and smoth out the welds for a finished look.
you cand grind the welds all you want to make a reweld for good penetration or a weld that has craters in it from contamination on the material. allways clean the surface to be welded with a flap disc on a angle grinder. all roll bar material has a mill scale on it that needs to be removed. also use something to clean any oil off the metal.

DO NOT I REPEAT DO NOT USE BRAKE CLEAN to clean the meterial to be welded !!!!!!!!

The man is right. Clorinated brake cleaners produce poison phosgene gas when heated.

http://www2.worksafebc.com/i/posters/2013/ws_13_09.html