I bought a LWP low profile cover for my 12 bolt rear. I just worked out a deal to trade it for a 8.5 10 bolt that I wanted all along.
The LPW cover is THE BEST bearing support cover out there, period. This is the low profile design, so you can run a huge sway bar or have extra clearance for an axle tube brace, or whatever.
PN: 201-12.
Details for the LPW cover can be found here:
http://www.lpwracing.com/p_capcovers.asp
LPW lists them for $150+, so does Summit/Jegs...
$140 shipped and its yours.