Still waiting for the 1512 2.5d to get back in stock and the lipos I want. Until then, I decided to re-do the center top plate to move the ESC back a little and more to the motor-side so the wires will reach better without entending them. I was gonna throw away the old top plate but figured maybe someone else with a MBX5 conversion could use this to stiffen up the chassis. If anyone wants it, let me know. Just pay for shipping. I didn't take any pics of just the bar, but it's the one in the picture below:
Not pictured, but there is a scratch in the paint where the ESC goes because I trimmed the velcro with a knife.
If no one wants it, I'll just toss it...