Mini-z center shock mount

A mount to both attach the top damper plate and provide a mounting point for the common center shocks that are based on a sliding piston with 4.8-4.9mm ball., like PN-racing MR2161, XP-M03-DPS, ... This part will be lighter and more precise than the original solution. Most importantly it will lock the ball from moving rearwards. The fitment is deliberately a little tight so it can be finetuned to perfection for the standard PN 4.9mm steel ball-piston, but can also be used with the more commonly available and lighter 4.8mm delrin and aluminum balls.