New sending unit leaks at lock ring

Detroit Muscle Technologies sells a gasket that's the same material and thickness as the original, better than the ones that come with the repopped sending units these days...

http://www.ebay.com/itm/DMT-MOPAR-57-91-A-B-C-Body-Fuel-Lock-Ring-Sending-Unit-to-Tank-Seal-/360751319879?hash=item53fe744b47

Adjusting the tabs on the lock ring works pretty good too.