I agree about the Magura MT5's they are far superior to anything less than double the price.
I've found they work best with 203mm Icetech rotors and semi-metallic pads. very adjustable and consistently stop from >105kph
Fantastic build, that will take you anywhere.
Love the attention to detail.
My ‘Fatitty’ is identical with the exception of a 16S battery and nothing with a Luna badge 😊
Just a word of warning, if you have spacers installed for the brake rotor and spread the dropouts, your brake caliper may not align straight down onto the rotor. May I ask why you've chosen to install a 7 speed freewheel onto a high speed hub? You may be creating more problems.
You can use tools, but if your frame is in a jig or hanging from a sling it would just be easier and quicker just to manually spread with your hands and have a friend drop the motor in the dropouts. Don't forget your chain :)