440 duster. Need engine build advice

Hey guys. It's been a real long time since I've been on here. After a bout with health issues I'm finally back at it. I bought a 74 duster that I will be converting into a demon. The demon took a hard hit in the back left and is pretty well junk. So now heres the build. ... I bought a 69 440. Has new .30 over speed pro pistons all machine work done. Balanced ly rods. All new bearings. Set of 915 heads. And I believe the cam is a 557? It's huge. It has double valve Springs. M1 intake and a 850 demon carb. Now here is the issue. Cast crank. I have never built an engine with one. How do I balance this thing If the rodshave been completely balanced with the pistons? Do I use the factory cast damper? I have a forged crank that needs to be turned. But I have ran out of money and am looking to get this thing going. Should I wait to get the crank done or is this cast crank ok for a year or so.? What does this combo make for hp? Is there any thing I need to do to be aware of. What balancer do I use then? Any advice you guys have would be great! Thank you on advance guys. I will post some pics!