Def, take a look at the compressor map in the first post, 25psi on the 7163 will make 530hp at 7500rpm according to Matchbot. There's still room left in it too, it will hold that 25psi beyond 8k.
The 6758 just isn't going to have that top end flow since it maxes out at 7lb/min less than the 7163. Given that Geoff just confirmed the 7163 spools similar to a 6758, I can't imagine buying anything other than the 7163 for a 550whp or less build.
But don't buy a 7163 before me! I wanna be first
