[TRE Cup]

Conventional wisdom is that the closer to the motor, where the most heat is coming out the exhaust, the more efficient the turbo set up will be

BUT....I've seen the rear mounted turbos on Corvettes and a few knowledgeable people that drove ./ ridden in them were amazed how well the cars performed. The exhaust gases do cool off some as they travel down the tubes to the back, but it looks like that energy lost is no big deal when it comes to getting horsepower.
I would be curious to see how a back to back comparison would be on a road course. You might think the spool up would have a fair amount of lag. then again the turbos are rather small on these installs. Wonder where the cavitation points are