I have etrack in my trailer floor - if you spec it during your build process United (maybe other manufacturers too) will recess it into the flooring and fasten to each crossmember. That way it is out of the way and not easily damaged. Having etrack the length of the trailer allows for easy, load balanced tie down of other items in case you have something besides your classic car to haul. Also have them put something besides linoleum on the beavertail - it's too slippery when wet.