I have a part that is made of steel that I want to press fit into a part that is made of anodized aluminum. The shape of the press is shown in the attached image and the dimensions are roughly 0.5" x 1.5". My question is on how to tolerance each part. Should I simply use the machinery's handbook for an FN1 or FN2 force fit even though it is not a cylinder? I am also worried about how to keep the anodization on the Aluminum tight enough that the press works.. Any advice is appreciated. Also the thickness is a little over a mm.