My current 440 block had the cross-bolted 2/3/4 caps installed a couple of rebuilds ago. Even with an engine that only put at around 600 HP at its peak, there are signs of the bottom of the main caps that things are still moving around a little bit. Now it's gonna have to handle another 50+ HP and more torque, too.

My backup block has been machined for standard aluminum caps, plus I decided to add an old CRE girdle (similar to Hughes and 440 Source) to help stabilize the main caps better. No, it's not as sophisticated as the BCR cap & girdle combination, but it's what I have (and it's paid for).

You can probably tie up $2500-3000 in buying and "race prepping" a 45+ years-old OEM block w/ the BCR setup, once all the costs are factored in. Based on what I found recently, it would require close to $7K to have a ready-to-assemble BMP aluminum block. I'd love a new BMP block, though.