Dyno #'s with Trickflow Heads

WOAH
Do you like the power curve of the 268 Voodoo Range: 1800-6200; or do you want to go to the more converter lower gear route because that's where most of the suggestions for more lift than the .525 are leading you
You might talk with B3 racing to see if your geometry needs changing but most likely with the TF's you are ok if you got the right pushrods
but that's what I'd check first
check the sweep of the roller on the valve tip with some dykem or a magic marker and report back

another option since you have the roller tip rockers is to go to a solid cam
you can keep your low end and get some more top end
headers?
the Mr gasket head gaskets would help
what year 340
and what's your cranking compression
get the numbers and ask AJFORMS to run the numbers for you
then think about pistons or a cam change
now chill and get to work
at what rpm do you need more power?