I pulled the 383 out of my 66 windsor

[Cartel]

If there’s any ring ridge at the top of the cylinders that block will need to be bored out .030 and you’ll need pistons anyway. Are all of the rings loose on the pistons? After all the years and miles on that engine it is all but guaranteed that the cylinders are not round so even if the ridge isn’t extensive at the top of the bores it will likely need the overbore just to straighten them out and make them round.

there is a ridge, more on the low side and top than the sides so all of the above. some pins are tight too. the oil rings are sticking though.
the timing chain was super sloppy. I'm glad I parked it

 

[david hill]

Here is my take on how to rebuild w/ success. As @dematt said bore the cylinders .030 over. That will insure good ring seal also it will remove the ridge at the top of the cyl. bores eliminating possible piston ring breakage. As for your crankshaft, if measuring w/ a micrometer allows, micro polish the rod and main journals. Of course repalce the oil pump w/ new and the timing chain and gears. New cam bearings and camshaft w/ lifters is a must as both have a limited life cycle. If you don't do it now, you will later. Check the fuel pump push rod for wear. Notorious known for wearing at the tip, replace if found. Assemble your engine w/ high quality engine assembly lube and coat the camshft lobes w/ cam assembly grease. Any other questions you may have PM me.