Update. I did not hear anything back from HMB after I advised them that the cam chain tensioner does not fit my 2004 Ballabio.  Wanting to take advantage of the riding season I went ahead with using the HMB tensioner wear pad and spring on my original tensioner base. The pad is near identical and the spring as well The HMB spring had a little more resistance than the original, likely because it is new. They look identical.  I reassembled the bike, using new metal gasket on timing case, hopin