I make mine out of lite-ply...I cut hole approximately 2mm diamter larger than the boss on the front of the motor and then line the hole with a piece of silicon fuel tubing split longways. holds up well for many flights (100's). I've also used the integrated nose ring mount on a Venus II it was very good, but you have t beef up the firewall because the nose ring support cantilevers off of the center of the firewall.

Richard