Hi, Homefried1, I have the same tractor, with a 48" deck.
Yes it's the pulley slot next to the drive belt for the tractor.
From Hyper-Parts.com:
Dimensions:
Length: 102-1/8"
•Width: 5/8"
Notes:
AYP original part.
Replaces AYP #(s) 25672, 3555R, 6941R, 6941RR.
According to the manual I have, the same belt for the mule is the same for both the 42" deck and the 48" deck.
Yes it's the pulley slot next to the drive belt for the tractor.
From Hyper-Parts.com:
Dimensions:
Length: 102-1/8"
•Width: 5/8"
Notes:
AYP original part.
Replaces AYP #(s) 25672, 3555R, 6941R, 6941RR.
According to the manual I have, the same belt for the mule is the same for both the 42" deck and the 48" deck.