I have a 72 350 Olds motor I was going to take to the scrapyard. They require you to take off the oilpan, and upon doing this I am tempted to keep the Nodular iron crank for my 403. Is this worth the trouble as I dont know yet if the 403 needs rebuilding, but in the future if it does how much modification is needed to switch the 350 crank over to the 403. Any experience or knowledgable advice is greatly appreciated!