Big Block for the '67 has a mystery number up front...

[Gray Ghost]

First off this is a partial gloat. My friend has a 454 he pulled out of a 1981 motorhome that is going to find it's new home in my '67 stepside this year. I am trading him a deck for the motor [which had only 19k on the clock according to the owner who bought it new]. The deck will run me two days labor on my part and about $600 total in materials since I already have the decking at my house [reclaimed decking that's in good shape].

We cracked open the valve covers and found the inside to be very clean. The rear engine code says 14015445 which decodes to 75-87 or 90 depending on the site. Looks like this was a light duty truck engine. But the front code is weird....all the numbers look normal except for the 3 and the prefix code I can't find anything on is CBS [307369 is the rest of it].

Can anyone shed any light on that code?