Thanks montmil and Rob_Roller. The dimple is correctly oriented, I was aware of that, but have double-checked just to be sure I didn't space out on it, and it was correct. My observation of one of the four getting a lot more oil was based on manual turning of the rear wheel to reach TDC (OT) to set the valve clearances, which I checked enough times to move some oil. I've now run it briefly with the valve covers off and it is pouring oil from all four, with much heavier flow than I would have imagined, and while it is not uniform, it is heavier than I would have expected on all four rocker assemblies. I wonder if it could be non-uniform and heavy flow because of end float variations from one assembly to the next are giving too easy and too early an exit from the assembly? Should I be clamping the rocker blocks or pinching them together as I am tightening the stud nuts to minimize clearance, and if one does that is it possible to get the clearance too tight? I've read of a C-Clamp method at low torque, but nothing of at what torque to apply light clamp pressure.
This is a 1982 R65, and does NOT have the upgrade to 1985 and up rocker assembly with shims. I did loosely squeeze the rocker blocks while torquing them down, but did both sides at the same TDC - I did not rotate to the next TDC for torquing the second cylinder and head stud nuts (and the valves were not affected by the pushrods because the adjusters were backed all the way to maximum looseness when I torqued the head nuts, but of course I did rotate to the next TDC for setting valve clearance so each side's valve clearances were set at next appearance of TDC (OT) after the intake valve for that side had closed.