Originally Posted by Volvo Diesel

I believe only the '85 California models got the 722.4xx transmissions. The '85 federal models still have the 722.3xx (see the chart below, from the link that follows).

1985 FEDERAL W/S/C123 (300D/TD/CD) = 722.315 transmission
1985 FEDERAL W126 (300SD) = 722.303 transmission
1985 CALIFORNIA W/S/C123 (300D/TD/CD) & W126 (300SD) = 722.416 transmission (300SD had a different tailcone for electronic speedometer - 100% interchangable with mechanical version)

1985 diesel Mercedes upgrades - Mercedes-Benz Forum

From the OP's videos, it appears his car is federal spec., so the transmission should be a 722.3.