Derek nice boat. You probably won't believe me when i say this past weekend i have been gutting my 76 Grady Whitere Nassua. If you contact grady white ask them for your stringer layout. They didn't have mine but told me that the Chesapeake i think 72 or 74 was the same. Now with my style boat only came with 3 types of I/O's. my transom is 2 full inches but man i tell you this. the sole, and transom were bad. Like real bad. i gutted it out and will pull the i/o very soon. Im not restoring it to factory, im rebuilding it for my fishing. I believe id rather sink 10k in a boat and make it to me and my needs then buy a 10k boat and still add to it. Different strokes for different folks. I will post the diagram for my layout and a pic of mine for you to look at. Good Luck!!