No experience with having done this, John, but words of caution and advice.

1. Do not have the glider in or near the trailer when you do this. If you remove the front hinge, the struts are going to push the top forward. This will do bad things to your vertical tail and other parts of the glider.

2. Strongly suggest borrowing an engine hoist or similar, open the top, use the engine hoist to take the weight off of the strut to trailer attach bolts, disconnect the gas struts, use the hoist to gently lower the top, remove the front hinge bolts, use the engine hoist to pick up the front of the top so you can get in to replace the seal.

Alternative (maybe too "red neck" for your taste) would be to install a fabric seal inside the trailer between the top and bottom parts across the hinge. It doesn't move much from open to closed, and you can pretty well shut down air and dust passage through with a fabric seal.

Steve Leonard