Art, Gary Peloquin (
www.peloquins.com) now has a torsion style LSD that fits the A413 without needing the ring gear spacer the OBX or Quaife requires. It's a spendy one grand, but it has top quality German bearings and such. Several have used it and reported no problems. Unfortunately, I've been cash strapped for the last year, so I've not bought one yet.
Mark, I'll look into the high tack gasket sealer you've desribed. Anything is better than taking a jack hammer to a pan because the RTV is too good, haha. Thanks.