Any aftermarket one will work. http://www.6061.com/standard4150.htm http://forums.corral.net/forums/power-adders/1358389-wilson-95mm-tb-4150-intake-elbow.html
I a using the accufab 90 MM unit, its more than enough...You will have to make a custom throttle cable bracket no matter what..
Edlebrock. Wilson. 6061. Is there a difference? Edlebrock is alot cheaper. 6061 looks better. Wilson looks good and is a little more expensive. Is there a difference in air flow? Too many choices.
The only difference between any of the elbows is airflow distribution. The more airspeed you have the worse the problem. The right size charge tube and throttlebody for your hp affects this more than the elbow does. If you have a big plenum under the elbow that helps with distribution. Basically, pick the one that fits the best and has the throttle cable mounting you want and you'll be fine.