I got some time off today so I went to the shop with a buddy who works there and we worked on the 72 455. We measured the deck height and checked the balance on the rotating assembly. It doesn't sound like much, but it ate up a lot of the day and we were interrupted a few times.
The new pistons are sweet and only weigh 465 grams. The Eagle rods are pretty heavy but the bob weight is less than 2300 grams. For comparison, an aluminum headed, roller cam 454 that went out a few days ago weighed in around 2500 grams. The crank was cut 0.50 on the rods (IIRC) for the BBC rods so the rotating assembly is a lot lighter than the stock setup; this engine should rap up pretty quick. In addition, the crank is going to lose a lot of meat to make up for all these changes so it gets lighter still. ;^)
The heads aren't done but the combustion chambers are looking pretty good.
Here's a link to a couple of pictures: