Now I know you already bought the struts and stuff for the front but they really do create issues with rim selection. Have you thought about using some parts from factory five racing, the kit car guys, they have parts that convert the mustang spindles into dual a-arm units. they have done a lot of work making these stout and setting them up for the track very easy.
I'm not telling you what to do but some times you have to rethink rather than compromise
Thanks for listening,
Patrick