Hi Guy,
I know you side you primed the piece it looks awesome!
If it's not too late ,or in the future you might want to try, after you clean the piece,
As you would normaley, instead prime it with sliver paint from Krylon paints as part of a two part priming system, advantages are, thinner particles atomization, can be brushed on, has good tooth as ground, and covers immediately, any color molding instantly, dries all most to the touch!
And all you have to do is give it a dusting with watered down light gray or white (XF2) Tamiya paint afterwards.
The relief will be crispier and sharper!
Try it some time, and let me know how you like it!
Happy painting
Alex