String mate,
I had EXACTLY the same problem - Hitler Salute to dump air, buoyancy goes to pot, spoils the dive.
My solution was to move the autodump about 4 inches backwards and 1 inch up. I used two-part glue from a mate (used to patch inflateable boats) but I believe Aquasure will do it. I marked up a circle to allow the dump to get through JUST. I did put a patch of rubber from an inner tube on the outside to allow the dump to seal well.
The resultant hole I blocked with a spare Buddy dump valve (how about that for redundancy!).
The result is an absolute dream - I roll my shoulder slightly up and dump in a precise, easy way whilst remaining horisontal. Dive bliss!
Do it - you won't regret it... Unless your suit leaks of course...
