L.F., nice work on the elbow! Do you use a ball-end mill for improved flow inside? I heard another suggestion for 90 deg exhaust on Saitos is to use the standard 45 deg header tube and use it with the new style cast mufflers Saito is using. The new mufflers have the inlet at about 45 deg, so it gives you much more mounting flexability. I think the new mufflers are about 35 bucks plus shipping.
Pilgrim