Once the crank is out you hold the small end in one hand and tap that hand with the other hand. If there is a fair noise the big end is worn.
With your mixture mate, in the first pic with the plug still in the head, there is a shade of black on one side of the centre electrode ceramic. This is pretty rich, you want to jet to the point that the centre electrode has no black and is all brown. You will still be on the rich/safe side. If it starts heading into light brown your starting to push the limits if the weather is changeable!!
[EDIT] Mate I have so enjoyed this build I bought my own!!!!! This is the best thing I've done in a long time I'm having so much fun with it!!! It's reminding of times gone by when I was much younger and crazier racing an R6 Yammie. The fact of having an engine over 1n1/2 times a PB and with 6 gears......... LOL.