There is no 1953 truck manual at the link that Rusty kindly posted.
There is a 1948-1951 manual - it will be OK for your 1953 torque-tube questions.

http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0450.htm

It looks like your leaks are at the universal ball joint?
You have to disconnect the u-joint to install new gaskets/seals.

Inspect the u-joint - it can slide side-to-side in the bushings, it should not "wobble" in the bushings.

Here are parts you will/might need:
https://www.classicparts.com/1935-54-U-Joint-Ball-Gasket-Seals/productinfo/92-111/
https://www.classicparts.com/1940-54-U-Joint-Repair-Kit-1_2-Ton/productinfo/92-215/
https://www.classicparts.com/1940-54-U-Joint-Bolt-Lock-Clips/productinfo/92-222/
https://www.classicparts.com/1940-54-U-Joint-Bolt/productinfo/92-221/

If the driveshaft is loose in its bearing/bushing (at the front end of the torque-tube), report back here for bushing replacement.

Tim
1954Advance-Design.com
1954 3106 Carryall Suburban
1954 3104 5-window pickup w/Hydra-Matic
The 216 and early 235 engines are not "splash oilers" -- this is a splash oiler.