Alright. I'm grinding my teeth trying to find out how to install these damn things. I've got them in. Y pipe made up. Sounds great. Except the passenger side. It has a leak because the very rear bolt I can't seem to get to. I have it flush but I'll be damned if I can't get a 11 socket or wrench on it. What am I missing?

 

I take it you are talking about fitting a socket or box end on between the bolt head header tube so first question is if you using small hex bolts? Something like this:
https://www.summitracing.com/parts/arp-100-1110

 

This one is better
https://www.summitracing.com/parts/arp-100-1109