broken arm delay will work to your advantage. doing this as your first tour could easily
be disasterful (or not....). do as the others advise, load up and take some short tours.
overnighters, 3-4 days, then a full week.

you prolly will want to change your gearing. i'd go with a 22-32-44.

being 'fit' doesn't necessarily equate to an ability to do a long-distance loaded cycle tour.
i doubt arnold (i'll be back!) could have pedaled a loaded bike more'n half a mile. train
for what you gonna do.

get your buddies to train as well.

and think about actually, you know, resting on your rest days. get off the freakin' bike
and do something different. go hiking. go swimming. stay in a hotel and sleep.