Replacing back catalytic converter troubles

[Trinost]

I purchased some great catalytic converters from Eastern Catalytic off Rockauto website. I was able to replace the front cata with no problems with their eco III catalytic converter designed direct fit (it totally is ).

However the back cata is giving me issues I cannot seem to get the nuts off the three specialty bolts...I am wondering if the nuts are spot wielded on like the front OEM cata is. I took a torch to warm them up and then an impact gun and couldn't get them to budge at all. I only have normal wrenches and sockets and they are not gripping the bolts at all.

Idea's on how to DYI this before breaking my bank having someone else take it off and install the one I already purchased?

side note: also need to figure out how to get a rounded bolt off the EGR valve. I tried a go2 socket but it is too bulky any thoughts since such a tight spot?

[Daox]

I PMed you about this, but I'll put it out there for others too. I have a set like this and they work very well.

Craftsman.com