Since last night I have found the replacement bolt part number: W710540-S439, for my 2009 Mustang GT. I am sure its the same on all S197 mustangs. The discription says its a M12x1.75pitchx55MM flanged hex head. The hex size is a 10MM. I will scan this sheet in at home later tonight and post it. I also post the pics I took while measuring the entire bolt. The Ford dealer gave me the bolt, costs like $8 if you did need one.
I also found a replacement bushing kit from
energysupsensionparts.com, part number: 4.1131R (Red) 4.1131G (Black)
Says it fits 2005-2007 Ford Mustang, but sure it fits all S197 mustangs. Will definately find out and post results tomorrow.
CMAX