I'm thinking about changing the rear main oil seal when I have the tranny off to replace the clutch. From what I have read I need a oil seal install tool to put the new seal in the block. I've found a few cheaper ones on Ebay but they don't list my 2000 4.2L on the application chart. While trying to cross reference through searches I found that they will work on multiple engines/models including the 2005 4.2L. It appears that all the applications that they list are for 2005+.

Does anyone know if the seal design changed between the 2000 and 2005 model years?