I ground my stud, nut and pump to get them to clear. You should not mix studs and bolts on the same cap, if you are going to use a bolt on the rear main use two bolts.
Well I did what I did because that was what ARP recommended to do. I called their tech line after I ran into this problem. They did not say anything to me about grinding the bolt or stud down. I would think that the heat introduced with grinding or cutting would have an effect on the machining process that ARP goes through at least the proccesses that they go through to get them to stand up to the abuse. I don't know for sure how heat would affect the bolts or studs. On a side note I have put over 30,000 miles on this engine, and never had a problem. I did rebuild it recently but there was nothing wrong with the engine when I took it apart I just wanted to go faster. This time the shortblock was assembled at Hughes Engines a proffessional mopar builder, Dave made no mention about me mixing bolts and studs and that was going to be a problem. Not trying to start an internet war here, just explaining myself.