I am trying to replace my 1999 Accord's (4-cyl) thermostat and am having difficulty removing the clamp off of the lower radiator hose. I cannot get a pair of pliers, vice grips, or anything in there to loosen the clamp to pull the hose off. Any suggestions of how to do this? Should I remove objects in the way? Thanks.

 

Have you try a vice grip to clamp and keep it tight then pull the hose off?

 

I clearly says in his post he's already tried that.
If you really wanna get it off and never have to worry about it ever again, go to sears and buy the special clamp pliers for them. You will never struggle with another clamp like that ever again