As most of you know, I am going anal and using KD center-shank couplers in Accucraft gear boxes on all my Accucraft, PNG’s and scratch-built stuff.
To get the couplers to “roughly” height, sometimes a little cutting and filing is needed.
Once you are close, I discovered that I can use shim washers to bring the coupler right on.
These are placed on the truck bolster with a little lubricant. Raising your car 1/16" or so does not effect the look of it.
Accucraft trucks are metal. You can smooth up the bolster and it will swivel against the shim washers just fine.
I use a 3/4’ wide shim washer with the center hole the same size as the mounting screw.
Shim washers come in various thickness to adjust the truck height. ( Or you stack them. I had to use four on my PNG 40’ refer.)
Now if I have to lower the car a little, that’s a whole new ballgame.
Fortunately, I have to raise the couplers and cars to make the height gauge standard.