http://www.maperformance.com/jm-fabr...nge-evo-x.html
You can get this in 3.5" size or 4" size
I think it is just a matter of not letting the MAF read 5.0V and then Shane can tune around it however. Even if it necks down it shouldn't matter too much, the problem here is the fact the MAF is maxed. With a bigger pipe, I believe that the MAF sees less air since there is more room around it to flow and therefore it reads a different voltage.
You could probably even cut the AMS part way and transition to a 3.5" intake where you put the MAF and filter.
I am probably going to sell my AMS one and I could probably pay for most of the fab work for DB.