to flow above 8k you need a big ol' motha****in turbo
most 30r's can't even do that.
as far as the tach i'm debating doing it on the brz, it seems pretty straight forward. however for thee cars there really in't much you can do with the tach because i haven't seen any crazy JDM designs like the GD's have or any over lays...i'm sure you can make that work though, splitting the cluster is pretty simple.
here is a destroked 2.35L with build heads and a 35R ON PUMP with only minor fueling mods. if it were me i'd do this exact setup but i dont know how much a five speed can handle.
as far a the clock you can cover up that entire thing with a pod but i liked the time there, i know one member took his Accessport apart and put the screen in there instead of the MPG meter, thought that was pretty cool...saw a thread about it.