839401 is the head casting code for 1941-1948 216 & 235 engines.

As you saw in that earlier post/thread, DBA is the engine serial number preface for a 1946 3100 truck standard 216 engine.
http://chevy.oldcarmanualproject.com/chevyresto/4649.htm

Did you find the block and head date casting codes (shown in the link in that earlier post/thread).
http://www.1954advance-design.com/Web%20images/casting-code-photos/low-press-codes-ser-nums.html

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.