I assumed you were using GTA as I haven't seen any AMG things outside of the "A-Spec" special event's list, and wouldn't know where to get a tuned version of an SLS,
if your looking for 54 driver's and worried about their driving standard's, perhaps try this idea,
hold a race using the Zonda R from recommended garage, that is probably the closest we will get to the cars intended to be used inside the recommended garage, then use the circuit le mans 2005, 5 laps on racing mediums should be long enough,
BUT, I would assume all people that applied for a team principle position would have some very very good driver's in mind, be it out right fast, or just consistent, there re obviously people whom are not associated with a team, and I'm also assuming potential principles may not have a full team, so instead of doing a complete driver draft, allow the team principles to work out their team's and have the ones that aren't in a team as dedicated stand in's, I know most of he people who would be on my team and we probably wouldn't win it, but we would enjoy being in it, they are a clean bunch of guy's with a bunch of victories in their fields,