Flatening reef
If your existing main sail has years left in it, you could consider having a sailmaker add a flatening reef about 10-12" up the leech. When you tie that in, just dead end the flatening reef line in a loop around the boom, run up to the new cringle and then thread it down thru the end of the boom if you have an open reefing block at the end of the boom. If not add a cheek block and cleat on the side of the boom. With the flatening reef tied in, only the aft end of the boom will be raised and you will be set up for a little higher wind speed.Alternatively, I needed a new main on our 28.5, so I had the sailmaker cut the clew about 8" higher on our new loose footed main to lift the end of the boom high enough to clear a new Bimini. Works Great!