When its all said it done whether you do nothing or turn the car upside down, a closed cooling system is next step. It keeps the rad full (keeps air out) and the nasty off the street. IMHO
I would start the cheapest way. Go down at least 2 steps colder on your spark plugs. If they don’t foul (probably) won’t, go two more. You have to stop the pinging!
The old Mopar system was a great option at the time. Fast forward 50 years and there are better options. Only after I swapped out my Mopar system to HEI did I find that out.
Slantsixdan is one of the most knowledgeable on here. Click on his link and run the HEI he recommends. You wont be sorry.
Send that other crap back to eBay.
Ballast wire to the coil shoul be battery voltage at start and 9-10 in run.
Bypass the ballast by jumping it until you get the thing running. You should have battery voltage at all times. Start or run. Once she running, remove the jumper
Maybe a feel good thing but 91 octane has a slower burn rate then 87 octane so could be the car likes it. If it don’t ping you don’t higher octane.
Only way is to run both and see which grade returns the best fuel mileage. IMHO
Thats why i used the www.classichei.com setup by Trailbeast. Plug and play for a few extra bucks. No muss no fuss.
Little plug for ya Trailbeast and I dont even know the man