two different diameter pushrods in chevy 454

[pwrunt3pte]

I had a bad head gasket so I'm in the process of fixing the problem. I got both heads resurfaced and every thing has been cleaned up. I'm just waiting for parts at this point. When i removed the pushrods from the engine, on seven of the cylinders the pushrods were 5/16 in diameter and one cylinder had 3/8 inch diameter. When i did some research it seems that whom ever rebuilt this engine put pushrods in it for a small block????? in this 454. From what I can tell the bbc 454 is supposed to have the 3/8" pushrods. My question is can i just replace the pushrods in this engine to the proper diameter or do I have to replace rockers etc???? thanks