Peter,

The reluctance to go into gear occurred before the possible overfill of the trans. (should have been a 1/2 quart low before leakage according to spec) And bringing it to level (or possibly overfilling it) made it go into gear normally and perform quite well (freeway, a couple of complete stops, then highway) for 50 miles.

Since there is a heavier concentration of ATF on the passenger side and I could not identify a leak during idle, it seems logical to explore the servo possibility. Where would I look for directions to determine which servo is leaking? (I do not find much trans diag info on the CD, Haynes, or Bentley.) I have the ATSG manual on this trans, but have not had time to thoroughly dig thru it...the first copy I received had 8 pages missing.
This an an 88 300E with the 722.3xx box. Have not found where I wrote down the exact model.