The 283s did not have damper bolts, same as 235 and 261 cranks. So if your 283 crank has a bolt, it was drilled and tapped for a bolt at some point in its life. I drill and tap all of my 235 and 261 cranks as a matter of course so I can use a real damper installer instead of a block of wood and a big hammer.
A lot of guys will use this bolt to turn the motor around. And a lot of the bolts will stretch and brake as a result. So use the correct tool for turning the balancer.
So first thing, are you 100 percent sure yours was drilled and tapped for a bolt?
If you are 100 percent sure, you might try drilling the center for threads, largest bolt you think you can get away with, tap for threads, red lock tite and after that stuff hardens up, see if you can back it out with the broken bolt.
Another possibility, the bolt was probably one for a small block Chevy, 7/16-20. Drill the entire thing out for the larger big block bolt, tap and install a big block size bolt 1/2-20.
If it turns out it was not drilled for a bolt, and you want to drill and tap for one, here is a tool to help with that process.
He also sells one for the larger big block size bolt.
https://mrhotrod6.com/products/cran...t-sbc-283-and-327-cid?variant=1142530117
