There is a drill & tap jig that's available that is used to locate the holes you need for a block mount starter on early engines. It bolts to the oil pan rail and guides a drill bit to prepare for 2 or 3 3/8"X16 tapped holes. The downside is the cost- - - -unless you're in the engine rebuilding business, buying the jig for a one-time use will get pretty pricey. You might check with machine shops in your area to see if anyone has that item, and what they would charge to drill & tap the block for the later model starter. Don't get tempted to just eveball things and use the starter for a jig- - - -the chances of succeeding are slim to none! Starter alignment must be exact. I think the jig is listed in the Goodson engine rebuilding equipment catalog, and also the catalog published by a company called "Regis". Do a Google search for those companies.
Jerry

Edit:
Goodson lists the jig, but it's out of stock right now.

http://www.goodson.com/store/templa...amp;SID=a80bc2371007243396d0c5baecd0feb3

You can use your 350 block as a pattern to fabricate your own drill jig. Use 3/8" or 1/2" plate, and make a cardboard template to locate the holes you need. Once the dimensions are transferred to the steel plate, use a drill press to make precisely vertical holes in the right places. The tap drill size for a 3/8X16 thread is 5/16". If you can get the drill guide plate hardened, it will help locate the drill bit with minimum wear to the plate.
Jerry




Last edited by Hotrod Lincoln; 05/27/2008 3:11 AM.
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