Order of assembly ... Ball style end links
 

I am working on a bit of a project ...
Making adjustable end links from Ball style to newer style sway bar.

The order of assembly is: nylon bushing in end link, then use a BFH to pop that on the ball or the other way round ???

YMMV, but I would install the ball socket receive last. You don't need a BFH. Instead, a long crow bar will allow you to lever the socket onto the ball. It helps to do this with a loaded suspension (as on a wheel alignment lift or by rolling the vehicle onto a few of layers of 2x10's).

Sherwood

perfect ... thanks