I have to say I am sorry I don't know the answer to that exact question but ido know that I got a proportioning valve from a wrecking yard that was out of an s-10 pickup truck and I have an s-10 Balazer with the 4.3 vortec and it would not work, we would have had to cut and grind and weld and a lot of other stuff to get it to work so I would make sure I found out the answer to my question from someone I really trusted before I trust them if you have any doubt at all which it sounds like you do.