Hey Greg,
Don't know how I overlooked your ??? on chocks. Maybe you have it resolved. Any case, I did not open the underbelly to install mine. I use a chock that keeps the bike straight up even without tie downs until I can get off and secure it. The movement of the trailer will have the front tire sliding around (IMHO). If you rest the weight of the bike on the side stand, you are putting a lot of pressure on the floor. I would be concerned about damage there.
I also tie down the rear tire. I don't want that rear tire bouncing and believe me there is a lot of up/down movement going on behind the axles.
I hope you have found your unit as comfortable as we have. Looking forward to spring.
Good luck,
Darrell