PM 54A- shimming the cutterhead?

So I installed a Byrd shelix cutterhead on my Powermatic jointer (6") this weekend and it seems just a tiny bit tilted, cutting a little higher toward the fence side of the jointer. I was wondering if it's ok to shim one of the bearing housings (between the housing and the base) to raise one end of the cutterhead? If so, is aluminum foil an acceptable shim material (I'm thinking 2-3 layers might do the trick)?

Thanks,
Charlie