Any DS loop you buy will be fine with either a 1 or 2 piece shaft. people underestimate significantly what the stock shaft can take but, it's still a tier 1 safety piece in my mind. My stiffer's bolts directly to the trans mount, no hassle. It's a requirement at my track for anyone running a slick tire, regardless of speed.
2014 Premium GT, SGM, Brembo, Auto, Tech, Comfort, etc. GT500s, Steeda UCA, VMP auto N/A tune. 100 shot nitrous on BBR tune. Best e/t 11.38 at 120.85
2012 Premium GT, Candy Red, Brembo package, 3.73, MT82, Comfort, Tech, et al. Procal tune, Roush UCA, UMI poly LCA, GT500s, Steeda red bracket, Hoosier 28x10x16 bias drags. Best e/t 11.91 at 115.23 RIP