Islewis on your air lines be sure to get a set of airline restrictors from Robart. These will help your plane survive the slamming up and down of your gear. Will also help in the scale raising and lowering of the gear. Trust me these will work better than any wheel callor you can get plus more control of the gear. As far as the bottoms of the nussel start planking from one side to the other. Before you start though round out the back of the nussel round out and then start planking. After planking thick CA accross the planks on the inside then cut out for the gear doors then hinge. Use a small cable or dental floss accross the opening between the doors ( thread is attached to the doors not the nussel)when the gear goes up the doors will close. Make a small spring that will force te doors open. Works real good