Oh man, dont get me wrong I LOVE the header. It never came loose on my 1.40 sport, thats why I wondered if I wasnt doing something that I needed to do differently on the 1.60DZ. Im using the same header, I just moved it over from my other plane that was damaged due to hurrcane Rita.
There is no doubt that the female socket on the 1.60 head is a lot deeper. I was trying different things after the header came off yesterday and I found that I can completely tighten the header against the head without a washer between the head and the header, but I dont know if I should leave it that way. On the original install I used a steel washer that I had but I didnt know that you could buy a washer made for it. The one I have is more if a lockwasher and it eats into the header slightly. That was fine when it never moved, but if this one keeps coming loose its going to eat up the sealing surfaces on the head and the header, so I figured I would either find a flat washer or use no washer at all. Whatever you suggest is what I will do.

I have wondered if there were washers for that reason but I didnt see them listed anywhere on Centrals website. I have an order that should ship out tomorrow, I will email them and see if they can slip a few of these washers into my box.

Thanks.