Athearn F7A-B close coupling

I have recently purchased a couple of packs of Athearn RTR F7A/B sets and I would like to close down the coupler distance which is excessive. What suggestions do you have ?

use the short shank kadees.

Short shank KDs as mentioned above or the American Limited close coupling kits

I found a way of doing this with the Kadee #37s that are recommended for the units. On the non-cab end of the A and both ends of the B, you need to trim the coupler mounting pad a little - about level with the body - to allow the coupler to be placed closer to the bodyshell. Just make sure that the mountings don’t foul the trucks swing - I managed to get the rear of the coupler knuckle just clear of the bodyshell using this method, and they will still handle fairly tight curves.