'92 taurus tank removal

I have a wagon that's original owner lived in Michigan, therefore there is a lot of undercarriage rust. I'm in the process of putting new rear brake lines on and need to remove the gas tank. For the life of me I can't get the bolts holding the straps in place removed. One is loose but it takes several minutes of extreme exertion just to get a small turn out of it and the bolts appear to be @ 2" or so. At this rate, the Jetson's car will probably be on the showroom floors before I get the tank out. Am I missing something or should I just work out more? Penetrating lubricant and impact wrench are no goes. Thanks.

The only thing I can suggest is using PB Blaster or Zep Preserve for a penetrating liquid, letting it soak for a day or so. Then try tightening and loosening to work the penetrant in.