When installing K1D4-NC in the Kato SD70ACe, you will notice that the front slots do not have a bottom which causes contact problems during decoder installation. In the past, we suggested using solder on the copper tabs on the decoder but we received several responses from our customers saying that this solution may not work all the time. It seems to be a better solution to use a piece of white foam, cut from the foam insert in your Kato locomotive box. Take this piece of foam and press it underneath the decoder so that the decoder makes firm contact with the chassis.