Bleeding brakes on a Midget

I have a '77 Midget that needs some brake work completed. Because of a small leak, I have to periodically refill the master cylinder and bleed the brakes. The problem is, I haven't been able to locate the bleeder valves on the rear cylinders. My manual has perfect pictures on the front discs, but nothing on the rears. I thought I had enough mechanically ability to locate a small valve, but this one has me stumped.

Any suggestions on where this should be located?

I've bled many a wheel cylinder by cracking the tubing fitting to release the air (when the bleeder was broken off).

Sounds too simple, sorry I didn't think of it myself. Thanks for the help.