260 and 289 starters are different in length of the section that enghages the flywheel. I know because I ordered a 289 starter for my 260 and it did not fit.

Also, I remember there is a difference between starters for a manual and an automatic 289, maybe a 260 as well. I know this from the MKII I had in school and tried to replace the starter for the manual shift with an automatic one. Didn’t work again.

Fred Baum