'72 - Plymouth - Valiant - 198 - Straight Six - tough to start, and rough idle

Hi everyone. I'm pretty new to the world of A Bodies so appreciate any help or guidance anyone can give me would be much appreciated.

Car is new to me and while it ran, it needed a lot of work.

Replaced:

• Distributor
• Distributor cables
• Battery
• Spark plug
• Coil

Car was running great until driving it on a very rainy and humid day last week. Came to a stop at a light, car stalled and wouldn't start again. Had it towed back home and went through a lot of troubleshooting steps, and was finally able to get it to "start" but it was running really rough.

I put an inline spark tester on one of the plugs and while it lights up, it's not really bright. I did a spark test from the same wire to ground and again while it did spark it was pretty weak.

After talking to my mechanic he suggested it could be the ballast resistor. The didn't have one in stock so i'm waiting on it to arrive tomorrow.

A few questions:

• Is it safe to bypass the ballast resistor just to try to get it running. Wouldn't want to run it like that long term obviously.
• Are there other common problem points I should look at?
• Any good troubleshooting guides anyone could point me to?

Thank you