aluminum elbow coupling

[chevy42083]

Diesel shops should have it, They used 4+ inch tubing for the charge tubes

That was the problem I found.
3 is easy to find
4 is a little harder, but had a selection.
3.5 was difficult.

That applied to the couplers as well as the actual aluminum tube that I bought. I wanted it the full size of the MAF... not a 3in with a step up connector to the MAF. Although it looks silly big on there