7mgte + 6 spd?
 

is it possible? do they even match up? fabrications? any insite?

As far as I know, they don't match up, plus, you'll have to "convince" the trans tunnel to fit the 6 speed under the car, along with moving the shifter like a foot back. I could be wrong on the shifter movement though. Probably a completely custom job to do it in the end, nothing bolt on, so expect lots of fabrication.

It's been done. Moving the shifter was needed (I think the person I'm thinking of used a modified 1JZ linkage setup), expanding the transmission tunnel IIRC too... don't recall what else. From what I recall of the gearing I don't really see much point, it's like adding one more gear between the R154's 1st and 5th. There's a thread on here with info about it.. or it may have just had a link to a thread on another forum about it. Dig a little and I'm sure you'll find it.