Another thing,

Be careful what you guys buy on e-bay, there's a few AD's on ELT's like
Narco, Artex, Leigh, Pathfinder etc, all have AD's on one of their
models or batteries or whatever.

If you install an ELT with an AD against it in your experimental
glider, it still applies, regardless of what it's installed in. You
will still have to accomplish the requirements of the AD. Experimental
gliders are exempt from Part 43, not Part 39.

Jim