modify 65 column dual cable shift for later single shift 904

Was there much debris or residue in the bottom of the pan? What color was the fluid? I'm thinking an easy fix.
I don't see anything that indicates a burnt out transmission. I suspect something broke in the shift mechanism or the parking lock mechanism. Also noticed that the throttle position lever (kickdown) moves without any resistance like it's not attached to anything at the other end. I will look later and take pics of the internals.