Sort of self explanatory
Accompanying text below:
Potential Damage To Radiator Upper Tank
(1969 Mustang Equipped with 390 CID Engines and 289/302 CID Engines with A/C or Extra Cooling)
On some early built 1969 Mustangs, the radiator was not securely retained at the top allowing a fore and aft movement and could contact the lower rear corners of the radiator upper support bracket results in possible upper tank damage.
Inspect for the subject problem when performing pre-delivery and regular maintenance checks or on a customer complaint of a leaking radiator.
Rework the upper radiator support bracket by bending or grinding away the sharp edges on the bracket surface which could puncture the tank. This surface which appears in Fig. 8 is on the radiator side of the upper support bracket parallel to the facing the engine fan. After reworking the bracket, bend it down over the radiator to secure in place. The problem was corrected in production on all units built after November, 1967.