Does a IRS catback fit a SRA car?

The rear axle at full-droop would cause problems. In the IRS, the center section is fixed to the chassis and does not move so running exhaust pipes there is simple and elegant. In the live axle though, the whole deal moves considerably, pumpkin and all. I think you'd have no end of problems try to get that to clear and even if you were successful, the pipes would be so low that they'd be ripped off on the first good bump or raised manhole cover.