Personally, I would use the springs that Comp cams recommends. Most likely the edelbrocks would be fine, but I would still call comp cams anyway. At any rate, you are trying to wake up that 289, and what you are doing is the right thing to do. I would do basically the same thing to my 289, but she's a "C" code, and I don't want to spend all the money it would take to ensure that engine doesn't twist something apart. I use my classic for cruising, and my 03 Mach 1 to go fast. To each his own.