Correct Kadee couple for Walther's kit

Just getting back into the hobby and recently purchased a couple of Walther’s 50’ boxcars. HO. I had some Kadee #5’s left laying around after having sold everything off years ago. The #5’s don’t fit the “gear box” on the kit. When trying to attach the top of the “gear box” the copper thingie gets squished. Any advice?

Mainetrains [banghead]

You may be able to use Kadee’s “whisker” couplers (#148). These are a replacement for the #5s and don’t use the bronze spring that is giving you trouble.

Joe

These are a Godsend! I love 'em.