we used one of the KG`s 6-speed Dog boxes when i was racing Lakeside/QR/Morgan Pk etc back in the 90s,,, great box, but also "GREAT BIG" gears-shafts etc,,, very heavy, LOTS of rotating mass,,, heaps more "Oil-Pumps" (so to speak) & a difficult first-to2nd gear change as it was "hook-first" (so called cause first gear is beside reverse & then pull forward into neutral, then left & then forward again to get 2nd which is in the spot that first usually is)... once you`re in 2nd then you`re away & shift as per normal "double-H" pattern (because there`s another 4 gears to go
quick changes tho (apart from first to 2nd) & very strong,,, just WAY TOO MUCH inside the thing & a right pain in the butt to repair (which we have had to do on a number of occasions on both boxes,,, but once those dramas were sorted they`re very strong.
However---> i`d much rather a smaller gear kit & a sequential shifter,,,, oh that`s right , i already have that in my buggy now

(i know it`s cheating using a motorbike g-box)
Daryl (from KG) was a pretty smart cookie tho & made some pretty good things, the brown cross-flow mini went to one of my friends (Ken) who then later sold it on,,, Tony-> "Convertable mini" will know some more of where KG`s other bits went as he bough a pile of stuff from Ken
We have another one of KG`s 6-speed dog boxes here in Stewys Sports sedan mini (also bought from Ken)
& another friend of mine Bob kennedy from Murwillumbah also bought a 6-speed i believe
I believe that another fella by the name of "Attard" also bought a 6-speed dog box from KG way way back (1980s-ish) & fitted it to his sports sedan mini
so,,, there`s a few around
I also believe they (KG eng) made 5-speed helical boxes as well, altho i personally hadn`t seen one ,,, i think John from mini King was selling them,,, but all this was a long long time ago