Congratulations mate, it is magic country up there, you are going to love it.
I made the trip in 1985 with my brother, carrying all our gear on old XL500's and had a ball. Did it again in 1995, this time on XR600's, with my sister and brother-in-law tagging along in a 4x4 carrying our gear and it was even better.
Did the trip in a 4x4 in 1992 and loved it but not as much as when on the bikes.
Only advise I can give is to get very ride fit before you go, we saw a lot of guys struggling with fitness up there.