I've made many Cranks that can go that deep. You really have to be precise when making an oversized bill, if it is not perfectly square to the bait you will never get it to run true. You will also need to add a substantial belly weight near the nose of the bait to get that sucker pointed down, and you better have this positioned and balanced perfectly also. There are some tutoials that will add much more to this topic, do some searching on this site under tutorials, look especially at the one on making you own lexan lip, the one on adding belly weight, and mabye the Bomber tutorial, there is also a great one on balancing a bait with a model airplane prop balancer here somewhere, this will get you started. You may also have to use a heavier wood than Balsa to support all the added weight over time. Just my opinion. Sloegoe.