LINK 2119551 - Caterpillar

Illustration 1. 108-2146 Guard Group, Right Side ViewLH guards are mounted in a similar fashion.
Three possible configurations are expected:
1. Challenger 65 (7YC1-1538) Tractors. Remove 4E-0039 Brake Line Guard (See 3W-5207 Lines Group - Brake). These tractors were produced with a lower oil level in the differential case and used a simple rear-facing plug on both sides of the case. All of these tractors should have been reworked to the conditions described in Service Letter SEBE4306, dated May 21, 1990. These tractors require a rectangular cutout on each rear guard assembly which mounts over an elbow and standpipe. Insert a cutout at the proper location on both right and left hand guards. Also, each side of the case should have four bosses which are used to mount the brake line guard.For guard purposes, only the upper two on each side should be used.
The lower two bosses used for guard mounting (to be added) are the 3T-6090 Bosses. These should be located appropriately as described in Illustration 2, Illustration 3, and Chart B.
Illustration 2. Location of Bosses for Configurations 1 and 3. Right Side View.
Illustration 3. Location of Bosses for Configurations 1 and 3. Top View. 2. Challenger 65, Challenger 65B (7YC1539-2093) and Challenger 75 (4CJ1-435) Tractors. Remove 4E-0039 Brake Line Guard (See Lines Group - Brake). These tractors were produced with a higher oil level in the differential case and use a sight gage on each side of the differential case rather than an elbow and standpipe. A rectangular cutout on the rear guard assemblies is necessary to view the differential sight gage. These tractors have two bosses on each side to mount the brake line guard. Reuse these and add two 3T-6090 Bosses for the upper guard mounts. These should be located appropriately as described in Illustration 4, Illustration 5 and Chart C.
Illustration 4. Location of Bosses for Configurations 2 and 3. Right Side View.
Illustration 5. Location of Bosses for Configurations 2 and 3. Top View. 3. Inboard Brakes on Challenger 65B (7YC2094-Up) and Challenger 75 (4CJ436-Up) Tractors. These tractors also have the higher oil level in the differential case. A rectangular cutout in the rear guard assemblies is necessary to view sight gage. However, they have internal wet brakes so there are no existing bosses on either side of the case because there are no brake line guards. Four 3T-6090 Bosses will need to be located on each side of the case. Refer to Illustration 2, Illustration 3, and Chart B. 1993 Challenger 65C ( 2ZJ1-499), 1993 Challenger 75C ( 4KK1-499) Tractors
1993 For C Series, modify the guard as described below and follow procedure #3 for mounting instructions and boss locations.
An adapter plate must be fabricated and used to modify the 107-8321 (RHS) and 107-8322 (LHS) Guard Assembly For use on C-Series Challengers. Refer to Illustration 6 and Chart D.
Illustration 6. C-Series Adapter Plate. 1. Remove vertical portion of the unused mounting tab on the 107-8321 (RHS) and 107-8322 (LHS) Guard Assembly. Refer to Illustration 7 and