I ended up putting bottle jacks between the two frames and raising or lowering the MH until I had good access to the bolts. One would unscrew, but the passenger side one wouldn't release so I used a grinder and cut it off. Then it was just a matter of making sure the new bar was the same length, tacking it together, verifying it was the same length, and then burning it in.
When I put it back together I put new bolts in from the front to the back, opposite of the way they came out and still had to raise and lower the MH with the bottle jacks to get everything to line up.
It is not a terrible job, but not really fun either. I am not great at crawling under a MH and working in cramped spaces. If you happen to have a pit or a way to raise the MH the job just got that much easier.