[bigblockv6]

Yes you can replace the sodium filled exhaust valves with valves from a Caterpillar Diesel, I used to have the part numbers but long gone, they're either from a 3406 or 3116 engine. You can also go with some custom Manley stainless steel valves, it's a good decision to get rid of the hollow stem stock valves as they were notorious for snapping when removing the governors off any of the bigger GMC 60 degree family of engines and running them at higher rpms. You can eliminate the rotors since light duty 305 engines were not always equipped with rotators, then you would have come up with longer valve springs that are used in 305 engines without rotators. I'm using Ford 390 valve springs on my 478 V6 because of the higher lift custom ground cam but I did retain the rotators. What applications are the valve rotator eliminator cups for?