Nice project! I tried a RWD TC a few years ago and it was definitely a handful to drive. I started like you, with a shorty shifted back and my ESC behind the motor but the 63/37 weight ratio just didn't put enough weight on the front end. No matter what I did to the frond end, I felt no difference on the track. At 55/ 45 the car felt MUCH better. Lots of rear toe-in helped too. Anyway I like your projects a lot, keep it up!