Hi Dave
Just got my EFI machined, I milled the inlet down to 80mm off the manifold deck, next I plan on milling the port riser output from the plenum to about 50mm from the body of the plenum.
Once this is complete I then intend to turn the plenum so throttle body is facing rear and get someone local to TIG weld some joining tubes...
That's the theory! As mentioned before I'll probably balls it up though and be putting a thread up here in a few weeks asking for an inlet as well
Have you tried the Sierra Owners forum? I'm sure someone on there will have one?
Matt