Help planning trip to Fort Worth, TX, from Lansing, MI

For that time of year you should not need reservations. And weather could really have an impact on where you ended up on any given day. A couple hours before I was ready to call it a day I would look at a where I would expect to be. Then look at rvparkreviews.com for parks in that area with good reviews and call to see if they had space available.
Many things can cause you to run later than expected. I would not want dark approaching and know I still had several hours to reach where I had reservations.