I had this occur with my 41.  It was a failing coil.  On mine it would do it when it was warmed up.  It could also easily be an issue with the carb.  I would put a multimeter on the coil to check it as that is a free test.  

Pertronix ignition is infamous for leaving people stranded. My first suspect would be fuel supply, second would be the ignition system. I've heard from a number of people who either ditched the Pertronix and returned to the stock system or have the stock distributor and coil in the trunk "just in case".

@tiny Thanks Tiny, I’m suspicious of the fuel supply. Apparently Rochester carbs will warp and allow flooding. So I’ll try fixing the warp first to see if that fixes it. 

Add me to the stock distributor in the trunk when running Pertronix. It failed when running in the garage so didn't result in long walk or wait for the tow truck. I was the Ginnie Pig on a Chevrolet. The warranty claimed to be 33 months and  I had it 35 when it failed. Went back to old fashioned points over 10 years ago without any problems despite thousands of miles since the failure. Just last week it was 419 miles in Great Falls, MT area without a bobble.

@timothy-kruger it was the carb, I replaced with my backup and it worked.

@chip thanks Chip it was the carb. Apparently the carb is warped, replaced it with a backup and it runs fine