Sorry I didn't see this a bit sooner. But hopefully when you say summer, we're still not to your time down there just yet and this reply is still relevant. I have visited the Speedway a couple of times, and can say it is a good thing you are west of Jackson, as there are more KCS-powered trains on that end of the line. Much of the Speedway's traffic involves cooperation with Norfolk Southern on high-priority intermodal trains. There are essentially 3 pair of trains with some second sections thrown in-- the I-DAAT/ATDA (Dallas-Atlanta/NS), and then one set each from BNSF and UP. NS power shows up a good bit on the Dallas trains, but can be mixed with KCS or solid KCS. The others will be pretty reliably BNSF and UP.
There should be about 3 pairs of KCS manifests, all from Shreveport. One goes to Artesia, MS, one to Birmingham, AL on NS, and the other to Jackson, MS. These should predominantly have KCS power, and are often in DPU arrangement with power on each end.
I have not been that far west, but have friends who have, and many seem particularly fond of the area on the west side of Monroe, LA. If you get the opportunity to travel a bit, I would recommend visiting Vicksburg, MS to see the classic Mississippi River bridge there. Good shots from the visitors center as the eastbounds come off the bridge. You might consider visiting Shreveport, as that is the largest hub on the KCS system with a major yard and shop. Photos around downtown look good, but again, this is still on my "Want to go" list, rather than "I've been."
So to sum it up, I would estimate you'll see about 12-15 trains in any 24 hour period. The trains are very fast on the flat land. If you have a scanner, the KCS defect detectors are extremely helpful, even telling you in which direction the train is traveling. As long as you know at what milepost you are, you can quickly figure out when you have an approaching train. On my last KCS visit earlier this year, the crews were calling all lineside signals over the radio, as well.
Have a great summer!
Mike Derrick