@bob2 posted:You sure those centers cannot be soldered? Most look to me like plated brass. Nice work - I admire folks who can make Proto-48 work.
You are right, It is possible to solder them by machining off the plating – but applying a lot of heat to the centers is a bad idea. I tried one and the driver threw it‘s tire. Not the insulated one, it just lost it‘s press when cooled. I fixed it with loctite nasty green stuff, fortunately prior to machining. So it’s CA or epoxy 2k glue.