and this can be done with the TS55 and guide rail, one of two ways. I definitely think it's easier and faster to run it through a table saw, but since you have to make due with what you have, here are the 2 methods.
First decide whether your "keep" piece will be on the outside of the guide rail or underneath. If outside of the guide rail, you'll have to add for the kerf of the blade (actual thickness during a cut). You can run a test piece to figure that out. Just partially rip a board and measure it. Then add that amount to the final width you need ripped. Put some wood underneath the guide rail that's the same thickness as the wood you're cutting to keep it level and balanced. Mark the beginning, middle and end of the wood you're going to rip. I always do a middle mark to keep an eye on things in case I've distorted the rail or forced the saw over. Then make your rip(s) and your crosscuts.
If your "keep" piece will be under the guide rail, you'll need extra material to support the guide rail so it doesn't tip to one side during the cut. Just make marks at the beginning middle and ends of your wood that'll be ripped. Line up the edge of the guide rail and repeat the process as many times as needed, while keeping full support under the width of the guide rail so it doesn't tip. Then just crosscut your pieces to length.
You'll be more accurate if ripping all the pieces you need from a single length, in one rip cut with the TS55 since lifting and setting down the guide rail on marks multiple times introduces operator error.