Hello Stephen and welcome to UHE as we still call it: the unofficial husaberg enthusiasts site!
if you'd asked where to get parts from you would have had lots of little trolls help you out but as it is technical they tend to disappear rather quickly!
valve clearances are in the workshop manuals and there are old threads here about it that you'll have to search through the site for. there may even be a youtube video out there but be careful because the KTM clearancves are bigger. we are on a 1/6th of a turn.
good luck
Taffy