Need help with motor number

I think I posted my question in the wrong place before, so here I go again. I bought a motor and transmission for a man who said it was a 350, but turned out to be a sb400. The number stamped on the flat surface behind the alternator is SAXG 6983 which doesn't match any numbers for chevy I have found. I would like to find out what to set the timing to. It also has a mild cam and I' m not sure what else.

 

8 to 10 degrees on a mild stocker will run fine.

 

Thanks for your response, I will try to move my timeing.