When I saw ALJR's thread Another option for 3800 air cleaner, I liked it. Stock look, more air flow, easy to change filter and I could point it at the 3800na boot. So take a look at ALJR's thread to give him some props.
The can is hard to weld because it is so thin. Don't bust my chops about my welds. Should have done what ALJR did, tack it and use JB weld to seal the seams.
So, here is the base with a 3.5" pipe in it versus a stock base.
3.5" pipe with the hold down in it.
Here is the stock can with 3.5" out.
You've got to grind the bottom of the can out too
Here is what the 3.5" pipe looks like on the filter. I know, the filter is rusty. It was and old one in the trash...
Getting the old rod out of the base sucks. I just used threaded rod to replace it.