That changes things. The flat band probably looks like it's a third part but it's actually part of the face side of the wheel. Here's some pics to show the two halves of the RH-5° and how them connect. Stu

http://i286.photobucket.com/albums/ll89/truckdog62563/wheels/FirestoneRH-5degree004.jpg
http://i286.photobucket.com/albums/ll89/truckdog62563/wheels/RH5concaveside.jpg