I'll let you know when it's done as I'm not sure yet
Asking prices for W58s seem to be around £300, which is similar to T50s so you can offset that cost by selling your T50.
I got a clutch plate made for 75 delivered so that wasn't too bad.
I'm not sure how much the adapter plate will be as the guy's still working on it...
I've got the front part of the Supra prop which may bolt up to the rear part of the 86 prop once the flange is redrilled, worse case I'll have to get it modded by a prop maker.
I'll bash out a mount from some angle or something, and the other bits are an adaptor for the thrust bearing and modding the release bearing carrier .
Basically I'm copying what this guy did
http://www.aeu86.org/viewtopic/not-so-diy-made-a-t-50-bellhousing-to-w58-transmission-adap/t/9245