['68OrangeSunshine]

With the PerTronix ignition you should be gapping your plugs at .045 just like HEI, or any other electronic ignition. [.035 is for points only.]
Ignitor I or II?
I use Densos now that ACDelco went South of the Border. Their QC fell off the face of the known universe.

Also what viscosity oil are you running? For the Southwest [I'm in Tucson], I recommend straight 30 SAE. I run Valvoline Racing [VR1] SAE 30 in my '68 292 L6. Engines of this vintage were designed to be run on straight weight oil.
On my last 292 (that went 250,000 miles) I started out with 30 weight, then 40 weight after about 150,000, and finally I was blowing blue smoke rings of pure 50 weight coming up on 250,000, when I decided to pull it out and rebuild.
What do you estimate the elapsed mileage at on your 250 L6? [More miles, the thicker the oil.]