Yes, they are interchangeable (at least with early-ish 240s)

I have used a 244GL wheel in my '74 142 (and it also fits a '72 142) and also a '74 164E wheel which is in it currently.

One issue though - in both cases the padded rear part of the steering wheel (if that makes sense ?) fouls the plastic steering column shroud on the 140, so the shroud needs to be trimmed (or just left off completely !) to allow the wheel to fit. Not a major drama though - just take the Dremel to it...

I had the same issue with a MotoLita wheel which fitted a '72 perfectly but fouled the shroud on the '74.

The wheels have the same spline, but the shapelength of the back of the wheel is larger diameter so it wont fit into the standard shroud. I think the shoud must stick out further on the later model 140's compared to the earlier ones.

Hope this helps !

Dave