Um... turn the input and count the output turns?

Can't help with the oil but someone at w116.org might be able to, there are a bunch of 6.9 owners there.

Michael

__________________
Usta haves '69 250/8, '76 280C, 1971 250C 114.023, 1976 450SEL 116.033
Current have, 1983 300SD 126.120