You mean they can survive the basic L67 anyway?

From what I understand, the 60e and the 65e are basically the same transmission. The parts are close but not compatible. The other difference is the pressure solenoid, electric in the 65e and vacuum controlled in the 60e.

Yep. They are pretty much the same.

The 60-e and the 60-HD have minor changes in the valve body, different accumulators, but that'* pretty much it.

The 65-e and the 65-HD are pretty much the same except the HD has a larger differential. The 60-e/HD and the 65-e all have the same size differential.

The 60-e got a stronger single chain and gears (65 guys swap them in), vac controlled line pressure, but a weaker pump.

IMO, you can safely run a 60-e behind a L67 just so long as you aren't doing 1 wheel burn-outs, don't go much beyond stock power levels, don't rev much higher than stock(60-e pump doesn't like high rpm), and generally don't beat on it.

If you want to make some power, there are far too many upgrades and hard parts available for the 65 to not swap that in.