Tres, the 307 came from the factory with the same stroke as a 327 which is 3.250. The 307 was created by merging the 283 bore and the 327 stroke.
Gearheads, the idea would be to use a piston with higher compression height to compensate for it, such as the pistons out of a 283. I used to keep up with all the tricks but since I never come across any 307's I didn't care to remember. When building a performance 307 there's one problem we run into and that is the pistons. The stock compression height 307 piston from the factory is 1.675. The hyper aftermarket pistons are 1.655, so as you see they whacked .020 off the compression height. The majority of cheapy "rebuilder" pistons are made this way. That is why we use the shorter rod and a 283 piston which has a higher compression height due to it's shorter stroke.
When you look at my post count I hope you realize I didn't start turning wrenches yesterday. I say that because if I didn't know by using a shorter rod would cause all kinds of deck problems I wouldn't even bother to be on this site and I sure as hell wouldn't answer any questions based on something I know nothing about and make myself look like a fool.