Remove Tire from rim of hand truck

It has been said that you can find information about anything on the net. Well just do you know, that is a load of bull. Several things I have tried to find information about is not out there. Always seems that the situation I am in the need of finding a solution for does not exist. Searches jump all around what I need to find.
This hand truck has one tire that always goes flat so we got some tubes to put in them to quit the aggravation of it going flat all the time. I tried and slammed my hand so many times that I was at the point of pitching the damn thing across the shop. I stopped just short of taking a sledge hammer to it and smashing it flat as a pancake.
So I walked away from it before I got to the exploding part to search the net. All the results come back about getting the whole tire off the axle. That is not what I need to know. Or how slime does not work. SLIME, I did not put anything in about using tire slime, I put in getting tire off hand truck rim, not getting wheel off or tire slime or changing a truck tire or buying a new wheel assembly or anything else the search throws back. I need to know how to get the tire off the stinking rim. The tire tools I have, and I have used them many times over thirty some years, won't work. You get one tool in then the other and after that there is just not enough room to get a third one in the work around the wheel. The tire gets to tight on the rim that no room is left. And NO, I don't want to take it to a lawn mower shop because the cost of getting this done to both tires will cost more than the stupid piece of s#$t is worth.
The rim is in danger of bending if I apply to much more force to it and the rim bead is already getting chewed up from the tools.

To tell the truth, I am on edge about other things and the seemingly simple process of doing this tire deal is about to push me over the top.