Quoted from flynnibus:The smaller ones should just be different sized side rails - but the 72" has more deltas because it's rated for heavier weights. I've never heard of any conversions (tho I'm sure the company could sell you parts).
If you are sweating your grip, you probably aren't balancing the load very well.. it should not take a lot of effort from you to hold the cart.
Of course it's just a simple electrical switch so you could rewire almost anything you wanted in there, but I've never heard of any interest in upgrading it.
Sounds to me like the 60" length is causing you to reach too far under the load making it harder to handle? Might be better to try to sell yours and just find a bigger one.
I have the 72" and dislike the weight of it, but I can see how the 60" could possibly be short enough to cause different challenges..
Yeah, seems like 66" is about perfect when it comes to regular appliance dollies. The rails cover the full length of the game, and give you a extra to work with at the top. But it's still not so tall that it's hard to work with.
I imagine an escalera would be the same way, but maybe even more so.