JRV,
In the FWIW category,
JRV,
In the FWIW category, I had a similar noise show up on my BB, shortly after the rebuild was completed. At first, I thought it was a tensioner bearing coming apart...yet I couldn't pinpoint the noise source...just the front of the engine area near the crank. Oddly, the noise would subside as the car warmed up. My next thought was an arcing spark plug wire/connector end...yet, the car ran fine. In the end, the problem turned out to be a glazed over Polyflex belt for the alternator. Although the belt was reasonably new...and looked good, it would snap and crackle when cold.
I'm not familiar with the 360, but if Polyflex belts are used...it's worth a look.
Regards,
David