6B 1039 is a good Caterpillar number. Cat still has them.
Scott
Original belt is a 2B463......vintage Gates #104TG (45 in. x 1-1/8 in. x 42 deg.)
Cat does show the 6B1039 as a replacement but size is a bit different.....vintage Gates #674T (45-3/8 in. x 1-1/8 in. by 42 deg.)
Info according to the Gates catalog.
Thanks gents for the part numbers