factory installed clock

Personally, I think that NOS clock on eBay for $201 is a good deal, if it works. I had a clock from my Sport Fury rebuilt with a quartz mechanism, and it cost about $150.

Fifty years ago I had a clock in my 68 Roadrunner, and after a while it didn't work. Back then, if they had to go into the instrument cluster, it was going to cost $300. I don't think the clock ever got fixed.