Interestingly, when Fred Asbell wrote about longbows in Instinctive Shooting, he voiced the same issue when switching from recurves to longbows, because the way he grips a longbow puts his hand further away from the arrow than when he shoots a recurve.
The answer is, just shoot the thing, and let your brain figure it out. Most people shoot a recurve with the same natural cant 99% of the time, so any error introduced by the distance between your hand and the arrow is constant, and pretty soon you don't notice it.
Even when you cant your bow more than your normal cant, if you cant your head to match the cant of the bow, the arrow still seems to go where you're looking. There may be an error or an inch or so, but frankly, if I'm within an inch or so of my mark, I consider it to be a hit. The error is not an angular error, which would increase with distance, but a constant error, so the 2" error stays 2" as the range increases, so is soon lost in the variety of other errors that I introduce in my shooting.