Hey Deprived!
Remember, the "402" Blue Ox bar for E350 and early E450, AND, the "450" for later model E450's are BOTH NOT bolted to the pumpkin. The webpages linked above show a "typical" track bar. 402 attaches to the passenger side shock absorber mount. 450 attaches to the passenger side sway bar bracket. Because adding the 450 bracket to one side would put a twist on the sway bar, there's a corresponding spacer for the driver side bracket. I think I could have used a 450 on our earlier E450 that calls for 402, unless those sway bar brackets are different and they well could be.
My guess is that the interference with air bags is with only the driver side, where the Frame Bracket clamps over the Chassis Rail. That bracket is the brains of the track bar. I looked at the OEMYS stuff too, and the tightness up there dictates welding since there isn't room to get in and drill. There are NOT holes up there to take advantage of.
I paid far less than the price on that page of Blue Ox products. I forget where, but perhaps could find the transaction in files. I bought the Blue Ox because it was at the vendor that priced Blue Ox TT402 for less than other vendors priced Super Steer SS402. Blue Ox is Black, Super Steer is Blue, forget the brand Brazzel sells but it's Red.