Best way to remove truck battery?

[Esaias]

Need to take out the two batteries from my truck. Problem is, both positive cables are rusted tight. The bolt/nut on each will not loosen. I think I rounded one of them. (!)

I really really don't want to cut the cables and get new clamps, I've done before on other vehicles and always had problems afterwards. Any ideas?

I don't think I can get a hacksaw in there without tearing up the clamp.

I'm really hoping I don't have to replace the cable ends. Those cruddy clamp sets at AutoZone always seem to have issues after being installed...