You need a crank extractor to remove the cranks. If you don’t have an extra crankset to experiement with, then you won’t need one, but you might need a wrench to tighten the bolt on the axle.
OR instead of the nimbus i could get this (see pic), i have allways wanted to build my own wheel and customise a uni :), i know this isn’t all i need but if i buy the spokes and tube at my LBS i won’t notice the extra price 
if i got the nimbus the first thing that would give way would be the rim(me thinks) and for me the KH 29er’s hub and frame as cool as they are, are overkill, so this would solve my problems.
i get the tyre and crank length i want and a better rim.
Don’t forget to add the cost of the wheel build. Unless you are skilled at wheelbuilding it’s worth paying extra for a well built wheel at your LBS. That’s what makes a wheels strong, not just having a nicer rim. Better also check you got the right size seatpost. Last time I looked at a Nimbus the seatpost was skinnier than 25.4. What are you using for a seat?
Anyway, looks like you’ll have quite a decent 29’er based on that set-up 
Have fun!
nope it takes a 25.4 seat post.
i have never built a wheel before but i would really like to learn i don’t care if it takes me a week to get it right. is this a bad move, should a pay someone to do it?
i have a spare yellow seat that i would put on this beast and i am thinking of some yellow pedals
Building wheels well takes more patience than skill, and most local bike shops do a poor job. So definitely go for it if you have the patience (as most unicyclists do).
I just built my first wheel based on a KH29 rim and a UDC wide cromoly hub. It took me a couple of hours carefully following instruction and I think it turned out quite nice. I found tons of instruction in the internet and had access to a book, “The Bicycle Wheel” by Jobst Brandt that was helpful. Just take your time and tension the spokes correctly. It’s very satisfying to hold a wheel that you just built in your hands.