For my 3.4 swap I used a 987 air box and maf housing. The maf housing is smaller than the 3.4 tune expects but it seems to be within tolerance for it to adjust. The only custom intake tubing you'd need is from the maf housing to the throttle body. Makes for a clean stock fit/look and provides ample air flow for the larger engine.
Here's a good thread on the details.
987 v 986 Air box