I'm planning an 818 build which will use a Tesla Model S drive unit in an 818. I know it's been done, and should fit. My question is on the rear spindles. I know I'll need custom axles to go from the Tesla transaxle to the hubs. I have to find out the diameter of the normal Tesla drive axle. I'm not going to use a donor car, I plan to just buy the parts I need, so I have freedom to select whatever rear spindles I want. Are the 2007 WRX STI rear spindles compatible with the FF rear suspension setup? Will they take this kind of torque? Are there better choices that would be stronger? Total weight should be around 2600 lbs and I'm thinking of sticking with the FF wheel & tire recommendations. Any advice would be greatly appreciated.