This post is actually a couple of weeks old, but I never got around to creating it. So this shows a few steps in the process of preparing a Multipass kit.
This is the raw stock I purchased from the hobby store. It is ribbed styrene.
I use a t-Square to cut the stuff into strips, then use a great little tool called "The Chopper" to cut measured lengths of it. One of the great things about the chopper is that you can clamp down a stopper, so that all of the pieces come out the same size without the need to manually measure each one.
And here is the final piece, and where it fits inside the kit.
I also used the chopper to cut to size some styrene strips that are used as the little red wire thing on the pass.