With a point in revives and decent +skills you could probably get enough revives with crushing blow to take out most of the HP, may take quite a few trips though. Mercs will die very fast, so you might want to use infinity yourself to help with -ve resist from conviction, or put it on merc if you can get him stuck somewhere so that he doesnt melee the ubers.
Take a 4x eth dagger so that you can hit the uber with poison dagger if you do need to leave, for the longer duration poison. Or get a mage to do it.
Conviction + trang wing + facets is probably enough damage once CB has done its thing, survival might be an issue though. use decrep unless you think you can handle them at full speed. decrep+clay golem+holy freeze merc and maybe some "slow target" gear if possible.