While looking through the Master Parts Catalog I noticed the 67-70 Mustang and 70-74 Maverick used the same U-bolts. According to the catalog...the 75-77 Mav had a 1/2" smaller axle tubes than the earlier Mavs. Could this be a typo?
The axle housings on an 7-1/4 inch housing are likely 2-3/4 and the 8 inch housings are 3-1/4 inches.
I notice in the Auto Krafters catalog it shows the 75-77 being 3-1/8". Whats up with the 71-72 Comet...why not 71-74?
Auto Krafters did not have a MERCURY parts number guide past 1972, so they are real hesitant to say what will work on a Comet after 1972. I told them a Maverick is the same thing, but I understand their hesitation.
I just checked my '74 and with calipers and came up with 3-1/4". The Granada rear end I have has a 2-3/4" axle tube...'74 Mav axle tube is 3". What month was your Maverick's birthday? Mine was born 9/73. Do you know for a fact you have original housing? Might be Ford used up the 74 stock and dipped into the '75 parts if yours was a late production run.