I wonder if the k-frame is also from an 86, like the rest of the nose. The '86 k-frame is shorter. So, it's hard to get corrected camber on lowered or 5-lug conversions. For a 91-93, with cc plates, it shouldn't be hard to get the correct camber. However, you're still talking about doing something that the car/front_end where not designed for.
So, the individual tolerances for any specific car can be such that even "simple" or "common" mods will not work without some additional work for that specific car. Often very general statements are made about mods. However, people should realize that any mod that pushes the factory limits/tolerances may require some "additional work".
For example:
Enlarging the hole on top of the strut tower
Moving or notching fenders
etc
For my '86, and for most '86 Stangs, there are a number of "little things" (that can be a big pain and near impossible to do by yourself) that often are done to lower the car, or for a 5-lug conversion.
For example, to put in the real/orig booster that came with the M2300K Cobra brake kit in an '86, the strut tower back seam must be folded over and welded. The strut tower to firewall orientation changed ?3? times since '84. For a pre-87, the strut tower is closer to the firewall. Also, the FCA to k-frame mounting points moved a few times.
The changes were minor. But, when installing springs, doing an alignment, caring if a tire/rim combo will fit, it all adds up.
If your k-frame has "punched out triangles" on the top holding in the spring, then if I recall correctly, it's unlikely a 91 k-frame. The ?89+? k-frames went to a welded on top cup for the top of the spring on the k-frame. I know that "some thread" on the other site has good pictures of the different k-frames.
That's about all I can think of.
Good luck!