Make sure you change your pushrods to 4-40. Others have had the 2-56 rods bend. None of the UCD3D's in my club (4 of them) have the hinge gaps sealed. The gaps are pretty tight though.

One thing we've noticed is that the bottom edge of the wheel pants takes a beating and cracks quickly develop (we're on a paved runway) You may want to put some glass cloth or carbon fiber around the inside edge.

2 of us have switched the cowl mounting screws for 6-32 or 8-32 nylon bolts with tapped holes in the blocks. Haven't come out yet.

Chris