Looking on the FDV site, they make a V4 "low profile, short" model 510 that is 12.5mm from from the top of the top cap to the plunger capture nut, versus 14mm on the regular model. This should increase clearance from the bottom of the 510 to the board edge. Looking at the photos of the installed 510, there's a good thread and a half left below the the jam nut (unless that is the short model, of course). And perhaps drilling and tapping the mod top m10 x 1 would obviate using the jam nut at all. And what do you guys think about placing a 1mm thick x 14mm ID o-ring under the 510, for those who want the connector to stand proud of the casing? That would be just the size to fit outside the two ridges in the atty well. Might seal the connector hole against those rassinfrackin' bottom air drippers that like to puke juice on you mod...