I somehow lost the nut cap that goes on my seat. However I cant seem to find anything similar online. Anyone got a clue what the part number is?

 

 

That don't look quite what I have. My seat mounting hardware has a bracket with 2 studs coming up and plastic washer as a retainer. The nut caps that hold the riders seat, screws on to the studs. That nut cap is where the passenger seat slides on to.

 

C'mon Joe, not my first rodeo. That is the part you need. Zoom in on it.

https://www.outpostalaska.com/oempar...R_FRAME_RAIL/y

 

amazon

 

I re-read your post. Your bike has had the same mod I did. I got tired of the nut being pushed out by the stud. I substituted a part from a heritage softail as you described. Gimme a minute and I'll find the version that will screw onto your studs.

 

Well, there you have it.