I thought I felt my ears burnin' this morning. Knew someone was talking about me.

The formula is take the bow's marked draw weight and divide by 20. That tells you how many pounds per inch to subtract if your draw length is shorter than marked, or to add if your draw length is longer. On the longer end, it only holds true until you hit the bow's stack point, where the bow starts pulling considerably more per inch than it did on the inches before.

It's not exact, of course, but it gives you a good ballpark estimate.

Best of luck to you. I know you're going to enjoy going traditional.