The 305 actually has a slightly smaller bore than the 265, 3.736" instead of 3.750". 305 pistons have almost the right compression height to be used with a 2 7/8" stroke and a 6" connecting rod. By using the 305 high compression heads with some porting and slightly oversized valves, the majority of the parts will be 40 years newer than 265 stuff, and much more available. The heads also have the bolt holes for modern accessories like alternator mounts, power steering pump, etc. plus a serpentine belt system and water pump from a S-10 V6 will bolt right on. The only tricky part is getting the main bearing bores adapted to the small journal crank, and there's a set of race bearings for that application.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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