We are working on installation videos to help out more, but in your truck, it’s two things. One, you want to line the bottom bolts up first, thread in by hand and then the top will lineup in place. Once all three are threaded, you can then tighten.
Second, on some trucks the floor bolt/thread locations are hidden under the carpet and under a piece of tape. You trim the carpet, remove the tape and then follow instructions above.
Hope this helps and give us a call, we really would like for you to use the bottom mounting locations for the rigidly it provides.