The "kickdown linkage" really only increases line pressure.

If it was babied then there is a good chance it's OK.

Really, though, if you don't know it's history the seals and clutch material is going to be pretty well shot unless it was rebuilt at some point.

I just did a '73 727 with 60k orignal miles. While it looked VERY nice inside there was evidence that the bands and the clutches were starting to flake after 35 + years of use and the seals were hard and brittle as well.