Dang it swa45 we are having the same problem now with the Pinasco air box cover. Did you try this DRT spacer? Half of the description is about the Pinasco air box cover and that the spacer will allow that with T5 filter but may require shock length adjustment.
Did you manage to get the T5 air filter fitted with the bigger Pinasco air box top? I seem to remember trying and failing, so went down the route of the Pinasco venturi thingy. It was a couple of years ago and I've messed with all sorts of configurations, so I could have imagined it.