Congratulations for the new FabKit model - specs looking good! 
Will the 60W tube fit the MK5 by chance?
Thanks 
Sadly not 
The laser tube is too big. (1150mm in total)
We are working on an upgrade kit though so you can switch to Ruida with LightBurn.
Even though there is a new Smoothieboard V2 shown on Kickstarter, you plan to switch to Ruida?
For the time being, yes.
Sadly smoothie stopped production of their boards about the same time they launched their Kickstarter. So we were left suddenly sourcing clones, which led to problems.
We looked to other opensource boards but without the time to really test we decided it was best to switch to Ruida for the kit as the FabCore and FabPro were already using Ruida.
We will likely look to reintroduce the smoothieboard v2 to the FabKit once a stable board and firmware become available.
Although now the Fabkit Mk6 uses larger, higher speed stepper servos it would be a waste to limit its rastering speed to smoothies firmware bottle neck of 100mm/s (With Ruida the Mk6 engraves at 500mm/s ) Hopefully this is addressed in the V2
Kind regards,
Bonne