440 Oil pump drive

[MWFan]

Installing a refreshed short block in my 440. The oil pump shaft was scored where it runs on the bronze bushing so I bought a new one from Melling. I used the old one to make an oil pump priming tool, cut off the gear and welded a longer shaft on it to chuck up in the drill. Noticed that the gear I cut off was pinned to the shaft. The new Melling drive is not pinned. Is this a common failure point in a mild street engine?
Thanks, Bernie

 

[68Dart470]

Get the "pinned" one

 

[68Dart470]

https://www.hughesengines.com/Index...Q==&searchmode=partnumber&page=7&partid=14080