When I used to run a 440 6-bbl (both my Challenger and Road Runner had 'em at one time) I had home-modified outboard plates to allow using "real" jets. Not sure what a Stocker 340 would want compared to a street/strip 440, but I'd say have 62-68 for the center carb and 76-84 for the outboards. Even that will likely leave you w/ some jets that never get wet... but it should cover you across a pretty wide range of conditions if you'll be traveling around to different tracks.

In addition to Holley jets, I have the COMP MaxJets because they have smaller increments between jet #s and IMO can be better fine-tuned. They're similar in many respects to the BLP jets, too. Both the MaxJets & BLP jets are sold by drilled hole size and use a cross-reference chart to match them as closely as possible to Holley jet #s.

Good luck! Me luv Challengers with T/A hoods!