The '48 was an F-1 here in "up-over" and the rearend was a Dana that looks like a Dana 44 but is really a 36 or 38 or something like that. The '53-'56 rearend was essentially (dimensionally) the same. Anyway, Ford intro'd their own 9-inch in '57 and made some inconsequential changes during the first few years. The 9-inch from the early and mid '60s is a bit wider and might be what you are looking for. Do a Google search and you will probably find one of the several spec tables that have been posted in the 'net, containing widths, ratios, etc., like this one . . . http://www.maliburacing.com/ford_9_inch/ford_nine_inch.htm
If you are trying to get it as low as mine you have to get a 70's pick up rear end and get 1 1/2 spacers
Man that car is kick ****......and yes l'll be going that low (well nearly anyways). Thanks for the info guys. Mule, you gan go that low on me anytime....******x you big hunk'o'man you.
The F100 9-inch rears are the same width from '57 - '72. They got wider from '73 on. Check this out: http://www.hot-rod.com.au/builder/technineinch.html
Jugghead., I used a 9" from the first series Ford Bronco's(1967-76 or so). I don't know the exact width but it went under my 32 Roadster with plenty of clearance (1-1.5")on the inside of the tire but wasn't too wide. It looked right. I was running fenderless with steelies and early ford hubcaps. I used the stock 32 rear crossmember and spring. These rearends have the 5 on 5.5" bolt pattern for early or ford truck steel wheels. I got the hole rearend(drum to drum) for $100.00 and it turned out to be a 3:50:1 posi. Good luck Sam