have a 67 coupe with 5 lug drums on the rear and 4 lug on the front, had a set of 5 lug drums and spindles off of a 68 given to me,will they swap right over or is there something i will have to do to make them work???? thanks  

I can't find the spindle listings, but there are definitely suspension differences between 65-66, 67, 68-69 cars. The spindles carry a base part number of 3150, if it helps.  

The V8 spindles for the 67/68/69 are the same. However, if you had 4 lug on the front then spindles aren't your only problem. Reference the 6 cylinder to V8 changeover article here at mustang monthly because tie rod ends, steering stop and centerlink are different on a six cylinder, as are the springs and sway bars. Probably a few other pieces I forgot.
http://www.mustangmonthly.com/projectbuild/mump_0007_mustang_front_suspension_upgrade/index.html