Good info on break-in: Break-in Tips

What BOR said is true but excessive running without load on new rings just isn't good.

 

I'm coming in a bit late here, but I'll second the idea of going ahead with installing the cooler and lines, driveshaft and fluid, in that order. You'll have 10 quarts of ATF on your floor if you add the fluid in before plugging the big hole in the back. There's a lesson I'll never forget. ;-)

I have an old distributor shaft I use for an oil pump primer, too. If you take the dist completely apart, the shaft comes out and with the advance plate off the top, there's a nifty little turned down area that fits very neatly into your drill. If you have a 302, just be sure you tear apart a 302 or 289 dist. The 351 and larger engines use a different size (larger) oil pump driveshaft, and it won't work in your application.