I thought they said series 3 was "backwards compatible". That's odd
Tools
Tools of all sorts are welcome. They include hand tools, power tools, automotive tools, welding, etc...
Initially they did - 100%. Later they clarified old top will fit new bottom but not vice versa. Idk about the larger boxes - just 26/27" ones.
Thats frustrating. I have a 72" series 2, I'm hoping the new box fits on that. We'll see I guess lol
You could also use a wooden panel as a spacer to get a series 3 upper box over the raised edges of the lower box. If you're worried about the top box sliding off, the spacer can be bolted to the bottom of the upper box so that the raised edges still function as a barrier to capture the upper assembly.
I thought about that, but am lazy plus craftsman was cheaper. And maybe a pinch of petty "screw you harbor freight" ; )