9 inch rear source question

i recently found numerous #'s of 9"s out in the local salvage yard ranging from old f100's f150s to older 70s cars and havent really been able to find a place online or in a book that talks about those years, from what i understand. , Ive been looking to locate one so when the 8" does break and i know it will ill have one ready.
 
yeap thats the site i was refering to wasnt to specific when it came to 80ish trucks but i assume this is what they mean 73-86 65.25 inches

the one I found that had Straight tubes no taper was off a 83 F100 axle Code WDM CM 2LL1 3.50 9 S3188

not tottally sure on the full tag cause it was very damaged