Well, suit yourself.
Tried to help, with my reply.
All that i can tell you is, others have bought that "kit" used it, and didn't have any difficulties with it.
That's how i saved the link, in my computers files.
There have been many, numerous threads about your issue, in the past, so maybe do a search and see what comes up.
No such thing as an "adjustable" proportioning valve on any of the A body line of cars, so i haven't got a clue what your talking about.
If you do have a 71, and then the "factory" valve will be this one.
And this valve was used from 70-76 on the A body line of cars.
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