I removed ~2.38mm from either side of the swing arm pivot area and also 2.38mm from the pivot/collars but after the bearings were fitted and the dust seals installed, it still needs just a little more clearance to fit inside the frame. I removed as much as I could from the left side where the roller bearings live and still have enough depth to allow the dust seal to go on and sit fairly flush. Not sure what I'm doing wrong but I ruined 2 dust seals trying to install them without mangling them even after greasing the seals prior to installation. The right side has a little more wiggle room for trimming and it looks like I will need to remove just a tiny bit more on the right side of the pivot for everything to slide into place. I found that, due to the close tolerance, the swing arm needs to be coaxed into place by inserting the nighthawk pivot bolt into the swing arm bolt hole in the frame in order to align the collars the final few mm to line up the collar with the hole...
This blog is just a place for me to record some minutae that some other person in a similiar situation may find helpful.