If you suspect a HG problem, combustion gas tests can be wrong sometimes.
I had a Honda civic that was doing the same as your LC.
Combustion gas checks came back good (I did several).
Pulled the plugs, all looked even.
No steam clean.
Borescope...
BTW, gen1 on the left, gen2 on the right. The gen2 head gasket addresses the most common failure points.
For OP, do you happen to know when one you have installed?
if no external leaks, then engine is using it. pressure test, hot. pull and inspect plugs, and fluids. scope the cylinders while pressurized.....look for clean piston tops, coolant tricking down the cylinder walls. start there.
even those tests also miss headgaskets issues. There are many different ways to test for a head gasket, it can pass 4 tests and only fail one sometimes.
I changed to Pertonix @ 10 years ago and have not had an issue. I like not messing with points and condensers.
I do carry points and condenser with me in case the pertonix fails.