Gear mech can be changed like in nitro motor, there are 4 streched holes on chassis, if you look carefully to pic you will see part of hole in chassis on rear clamp. Clamps made by CNC water jet cutter. But those clamps can be made any CNC Milling machine in any metal workshop.
Servo is standart in old design LSP servo posts made by water jet also but in new design i will use only ESC brake look how it work out, if it not satisfy me I will go for Low Profile servo. How i will attach I dont know it yet.
I made battery box from double sided PCB, Cut pieces by CNC router, weld it and reinforced it.
I hope in march I will finish my Truggy