If you find a shop that works on radiators they can usually dip the tank and get it all cleaned up for you, often times preserving the paint on the exterior was well (don't ask me how.)
If you're willing to travel a bit there's a radiator shop on Airport Road between Baldwin and Cornelia (about 35 minutes north of Athens) that cleaned up a tank for a buddy of mine one time:
1047 Airport Rd Cornelia, GA 30531
You might be a KLR owner if:
You think mud is a good paint protector
Winterizing just means putting a tarp over it till tomorrow
You hit Home Depot and Tractor Supply for parts before you go to the motorcycle shop.
Every time you look at anything square shaped you think "Could that be a pannier?"
You like humvees and hate H2's
You've gone into an Army Surplus store to look for riding gear.