Without any doubt the zed would stay.
I would deffo play with subtle things like coilys, Nismo zorst, uprev etc but don't think I'd go FI.
After such mods I might even change it back to how I had it originally, just Nismo kit and LMGT4s.
I'm sure I'd have plenty of contenders in my garage to satisfy the speed freak in me.
Would just have the Zed restored and maintained to concourse standards.