Need help to identify my motor

[4shongo]

I bought my 66 C-10 Service/Utility truck a few months ago under the assumption that it was a 1976 250 I6 (engine swap at some point). It has HEI. I bought a chrome valve cover off EBay and it looks nothing like what is on my engine. My valve cover has like a 2" wide flat area on the drivers side, the whole length of the valve cover. Hopefully one of you engine gurus can help me.

Passenger side, close to firewall 1st set of numbers:
CON 2

A few inches away from that set of numbers:
A228 (maybe S instead of 8)

Half way towards front of motor:
GM
84

Numbers on head(passenger side):
0896

All of these are hard to read, hopefully someone can help me identify what I actually have. Thanks guys