As fer the tranny I have the 3.0 bell with left side slave but the tranny is a 1998 taco rightside slave. The bell bolts up but the engine mounted end of the 3.0 bell is 1 3/32" shorter than the 3.4L so I guess I will have to cut out a matching ring to weld up to the 3.0 bell unless someone knows a particular year of T100-Tacoma which has the longer bell housing and a left sided slave?
When you say left-side, are you talking left side of the tranny as facing the front of the engine - I.E. driver's side? Cause I think we're using "left" in two different ways.
You're looking for a pass-side slave mount bellhousing to mount to an 95+ r150 tranny... correct?
I think you have two options - find an older tranny... or make a spacer. I'd personally recommend finding a 151 instead. It will bolt right up to your exising pass-side slave bellhousing and directly to a gear drive tcase equipped with 23 spline input.
It won't be cheap, but likely cheaper than having an adapter ring custom machined or custom bellhousing made...
bkg