Timing chain

One the chain sheared, link type not roller type, my theory... chunk of plastic (i found many pieces ) from the guide got between teeth and chain. Chain couldn't crush it so chain sheared.
Two, guide came apart and chain skipped a few teeth.
Three, nylon teeth on cast cam gear, 160000 miles nylon cracked away and chain skipped a few teeth ( anyone want to guess what engine that was? Hint not mopar)

Small block Chevy every 70,000 in PU trucks. Chevrolet made me a lot of money. Still won't look at one for myself 40 years later...