All of them used Walschaerts. The only real differences between all of the Mikes were the crossheads and side rod lengths, and sometimes also the eccentric. And then you have the older and newer side rod variations. The early ones had the built in grease cups. It built up to a point and then had a zerk fitting at the top. The later types could be put on in any manner. It didn't matter which way you had it, it still had a easily accessible grease zerk. Just look closely at the rods on some of the K's in Chama.
Some of them have a little bit of both. On one said it a mix of later and old, and then on the other it's all older rods.
There is no difference in the rods of a K-37 and K-36. But the K-27's and the 470's are of their own designs.
Does Precision Scale make side rod kit's or something?