M rear caliper orientation

[simonr]

I have a 1968 911 it has the dual bleeder M rear calipers. Do the bleeder nipples go up or down on these ? thanks

[rw7810]

bleeder screws should be up.

[djpateman]

Air bubbles rise, so the bleeder always has to be at the top.
If you have the dual bleed rear caliper with cross-over tube, then I am sure the caliper is an L type. The L, M & S refer more to the pad type than to the actual caliper. For example, the M calipers all took the M pad, but came in many different configurations with 38, 42 and 48 mm pistons, front or rear applications, spaced for vented rotors or not and several different castings.