What charger should I use?

Because you use yours as a portable unit I like the idea of the strain relief on the cables. In a permanent installation replacing my 6345, I could get by without it. I wonder if I were to solder the exposed wires together into a tinned strip and insert that into lugs. Would the solder melt with enough amperage flowing through the wires? I have used a propane torch before to solder brass lugs onto a jumper cable wire when I was using the eyelets instead of clamps at one end. They never failed but I could have just been lucky. Last thing I want to do is burn the MH to the ground.
The cables I have are pretty beefy. Designed to jump start a diesel from a vehicle parked behind it. 30 ft long and probably 12 to 15 lbs of copper, brass, and insulation. Thanks for the pictures BFL13.