If memory serves me, and it seldom does, I think the dealers were supposed to remove them but seldom did. I thought I read that somewhere.
When you get a tank boiled out and sealed they put a drain plug in it ... it wasn't there originally.
For those that still have the brackets on their cars originally ... is there a bolt in the bottom hole? It appears the frame may be threaded to accept a bolt from the bottom of the bracket as well. Thanks ...
I had to take them out for now ... they were banging on the exhaust .... I might have to alter the tail pipe somewhat if I want to put them back in ...