Here's one fix, albeit arguably somewhat extreme: cut the fecker in half! Note my '66 Super, second from left below:
Each cab is still really heavy, especially the top with the amp in it. I usually use my old skateboard as an amp truck when I use the Super. I didn't cut the amp up, bought it that way back in the early '90's for three Benjamins even. It then still had the original tubes, but the speakers had been replaced with Sunn Magna 108's-- whatever those are, haha. They sound good anyhow. In addition to making it a little easier to hump, halving the amp also gives me the option of using just the top half, as a 40W 2x10 combo, or pairing that combo instead with a DIY 2x12 cab I have with some Celestions in it, for a little more bottom. The 2x12 is also a little easier to move, as it has some nice casters.
Here's a pic of that 2x10/2x12 halfstack, behind me on the left of the pic: