It used to happen commonly on Plymouth 383 engines made in the late 60s, but it was the push rod that sat between the cam and fuel pump that frequently failed. The worst part was the rod would mushroom on top and then it was very hard to remove. Even if it mushroomed just a tiny bit (which usually didn't happen on that sad engine). People finally started cutting a recess on both ends of the replacement push rods. I have not seen this happen on Stovebolt engines, but I have seen pump arms fail...on aftermarket pumps. Good luck.

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end