swatter, You're right. You gotta access the bolt from the top of the transmission housing. I'm fixin'ta hafta do the same thing. A reliable tractor mechanic I've met has, so far, steered me correctly on everything I've asked him about my
BX2230. He said that you HAD to take the floor pan off of BX series tractors to replace that fan.
BTW, what part of Alabama are you from? I grew up around Ford City, east of Muscle Shoals (still have a farm there), later moved to Sheffield and went to Sheffield High School and then Auburn. Lived for 17 years in Madison County and Decatur (working for gov't contractor mostly for NASA and Army Missile Command) before moving back to the Shoals. Moved up here to northeast MO in '02 with my job, but can't wait to get back to 'Bama. Retiring in Nov. 2017, and then back to Sweet Home Alabama!