Did this swap recently. See #11 in the b/w picture. It was actually pretty easy. I popped out the center grill section (without snapping off the clips.!) . One bolt holding the tube is easy to get at this way. Also took off the bolt holding the horn bracket. Took off the hose clamp at the air box end. Had to wrestle with the original tube to get it off the air box, but it relented eventually. Then had to convince it to come out past some plumbing.
This photo I found shows the difference between the skinny OEM piece p/n 4670469 and the replacement I put in, p/n 5327424. I think the larger diameter part was at one time the OEM installation for the diesels and then in 2005 (?) Saab began using it on all cars. I doubt the difference in airflow is anything I'll notice just cruising around but this has been one of the easy mod's I've been wanting to do and found one of these larger tubes at the junk yard a few weeks ago.
Name:  intake tube swap.jpg
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