I am wondering if a 1999 carbed 88" fxdx ignition module would be compatible with a 1999 carbed 88" flht bike?

I would assume so?

My flht's ignition seems to not always work properly, and I have a good unit lying around that came of my fxdx so it would be convenient if I could just swap both units?

 

Yes, Both models share p/n # 32748-99C

 

Thanks, will swap units and see if that helps then!

 

It might not mount, but you can probably use it for trouble shooting. I did that on my bike.

 

Why wouldn't it mount?