I am trying to find out the correct Serpentine belt length or the belt part number for the Hydramaster CDS 4.2. Hydramaster told me that a 5061075DR is the correct belt but it doesn't even come close. I tried the 5061115DR(about 4" longer) and it is still short by about 5". Was Hydramaster just guessing or what? I want to know if you know what the belt should be for this Hydramaster serpentine belt(not the belt on the blower /water pump unit) but on the actual vehicle engine belt. Your help will be much appreciated. Thanks Gary N.