I spent my hobby time this morning drilling and tapping the five tank car center sills and just finished installing the couplers. It is very clever the way Jon designed the couple box to stay in scale with some of the coupler base exposed yet fit within the constraints of the box. I used long nylon #72 screws that will be eventually trimmed. My tap resulted in the screws being a little loose, so I did not run the tap all the way through, meaning the last few turns of the screws have more bite. The covers have a flange intended to match that on the center sill but they are so thin the do not line up. Tomorrow I will shim them all to get better alignment. There is very little room for the coupler to move laterally and I cannot tell if the centering spring really has any effect at all. In a very tight curve things could go awry. Those of us that have built the little PSC Van Dyke tank car as standard gauge following Richard H's RMC article in the 1990's will remember that coupler arrangement has very little lateral movement also.
