If there is one criticism of the kit is the use of .50 screws for the clamping hexes, just not enough material in such a screw for this particular application, and would like to see 1.5mm at a minimum if not 2mm.
For those looking at gearing for blinky classes such as 13.5 I would recommend a minimum spur of 68 teeth in 48 pitch...I have installed a 66t and get the desired ratio just, so 68t would provide broader gearing options.
I went with a 96T spur 64P. And around 49-51 pinion. Fits perfect, lots of room to go higher or lower. I run blinky 17.5 too. I get around 3.6-3.8 FDR.