The original spec for an '85 TD was probably Dexron II or one of the variants (IID, IIE). Dexron III which is what's still available today but sometimes not labeled as such wasn't offered until the '90s, IIRC. The only fluid I see still labeled as Dex II compatible is Redline D4 ATF. Dex III is backward compatible with Dex II so maybe other ATF manufacturers don't bother mentioning it.

Definitely drain the converter. What post says to not drain the converter? Why change only 1/3 of the fluid?

Sixto
87 300D