With dual RL01's you're going to be fairly
limited on space,
I don't know how old of a version of RSTS/E you'd need
to go with in order to get it to fit. RT-11 is a good choice
for a system with that limited of disk space.
RSTS/E V7.0-07 will happily reside on a single RL01 pack.
Depending on the program packages you install,
you could wind up with as much as 3MB of space free.
Add another RL01 as a public pack, and you're "living large". ;-)
His real limitation will be the amount of memory on the 11/34.
If he's got 256K, then he'd be able to run between 2 - 4
maximum size jobs without swapping, depending on the
size he sets for SWAPMAX.
T