Hey JR, Cain hit the nail on the head with everything he recommended. The wing mounts are in stock at both Amain and tower. It's worth buying a few sets. Like he mentioned, I have been using 2 part epoxy and coating the outside of the wing mounts. Once it cures it makes the mounts 100% more durable. I'm going to make a step by step instruction on how I've been doing it and put it on the main page.
Also on the ball cups, they are the exact same that your already using on your other rangy cars. I've been using a savox 1258tg servo for a long time in my cars and they work great and fit very well. I'm going to be switching to xpert servos here soon. I've heard good things.
On the motor turns I run, I've been running the Maclan MRR 6.5 and 5.5 in my car. I think I've settled on the 5.5 for both dirt and carpet. With 10 degrees of timing in the endbell and unusually high gearing (87/22) for a 5.5 she comes off the track between 135 and 150 with a fan on it. I've been very happy with their motors.