Barts110, that is a wicked ride you have there! Thanks for sharing it.
As you may have realised, we are bunch of detail freeks who are passionate about our rides. Please understand that we don't mean to razz you at all. The info you've got is fine, it's just that there is lots of other stuff people like
Anlushac11 and others know. I've seen these guys extract more info about Ford sixes than I'll ever remember!
Hang in there, and a big welcome.
There are details on various axle combos even if you are missing the tags. I'd say you have a 4-cyl diff, and you need to place the car on the deck and measure how many drive shaft turns to each turn of the rear wheels together. Do that, and it'll work out the diff ratio. I use chalk, and place 1, 2, 3 and 4 on each uni as the car is slowly moved along the road. I do this on my own, 'cause it often makes other people mega-p__ed messing around with this. Then I roll the car forwards or backwards, and count how many times I see the numbers. In most cases, you see 1 go past 3 times. Then you my see the last part of the 2, 3 or 4 go past. That makes it 3.25, 3.5, or 3.75 roughly.
Hope you understand this.
PS. Loved the headmods section on
http://www.freewebs.com/81mustang/headmodifications.htm
Not bad at all for a 15 year old!