How do I ID a 50mm intake

[sciroccos at earthlink.net (Jim Ruffi)]

I bought my 16V with quite a few aftermarket parts installed, but I wasn't
able to speak to the person who owned it when they were installed.
Consequently, I'm not 100% sure what's what.

As the topic says, I'm looking for info on US vw Euro intake mani part ID.
Yes, I'm also too lazy to look for part numbers; I figured youz guyz would
be able to tell me if it's that easy.

If not, would an OD measurement of the runners tell the story?  Anyone kind
enough to measure either and let me know?  I have my caliper ready.

TIA

Jim