Spark Plug recommendations??

Just about have my new engine done, and was wondering what plugs I should use? Wanting to stick with good old Champions, but not sure what heat range to use.

The engine is a 318
9 to 9.5 / 1 compression
Comp cams XE268H-10 cam (.477, .480 lift, 224 230 @50)
273 closed chamber heads, ported, 1.88 - 1.60 valves
LD4B Eddy intake
Eddy 600 carb for now
Factory ex manifolds for now (changing to Dougs headers soon)
TTI 2.5in exhaust, with flowmasters, and cut outs
Mopar electronic ignition conversion kit.


Thanks for any advice!!!!!!!!!!!!!!
I am no good at picking plugs.