[zagrot]

it sounds as if you are trying to make your suspension fit a pre-determined rim size, which is the wrong way to go about things. typicaly speaking aftermarket suspension parts have the same demensions as the factory stuff, so your suspension will have aproximately the same demensions after changing everything (unless you have a specific purpose in mind and custom build stuff to intensionally change the suspension geometry). remember that most aftermarket parts are designed not to make a huge impact on the suspension geometry because that makes instalation more difficult. i'd recomend that you do all of the suspension upgrades that you want, and then decide on a rim diameter/ offset (that's how deep the rim mounting surface is from the edges of the rim) and tire size that best fits your car. i'd especially recomend this strategy if you intend to lower the car (something stock mustangs need anyway, the high-water-truch look isn't that appealing) but remember this: if you want huge rims on a lowered car then wheel well modification may be nessecary. if you are not able to do this yourself then a bodyshop will probably be able to do the job, but the price may be high.