What winch model # fits a D69U

should be a 6n maybe or 6d or e model think the n seriesgoes on the u series tractors. Jason

Most common is either the D6N or D6C. I would have to check on fit up for the Direct Drive D6D & E but I'm thinking they will work also.
Biggest challenge is usually getting all the controls and if the drum is bare of cable, getting the proper cable anchor attachment can be a hard to find unless it uses a standard ferrule.

D6N was most common, but last U models had D6C. Later D and E winchs will fit so long as they came off a U or a D6B. stud patterns are same for all models. BUT pto shafts were different for tractors other than those 2.
Have seen some D6 9Us with carco model F and F7 winchs, but you would want to see them fitted to the tractor they came off.
All used a stand 'L' ferrule you want 3/4 or preferably 7/8 rope if your doing heavy pulls.

I hope the winch fits your D6.
Really just because want to see pictures of it and the install.
I would love to have the forestry winch setup for mine.
Might copy what you do eventually.
Chris

Here is a picture of the Hyster D6C mounted to a 9U. Got plenty of pictures of D6N & C model winches that are dismounted from the tractors
in case you need to ID something.