Hello everybody. I'm buying a 340 block in Brazil but to be honest I don't know to much about this blocks. What kind of details I need to pay attention?

I'm planning to build a Pump Gas N/A engine, 12.0CR, solid flat tapped cam, Victor Heads, Tunnel Ram, Steel main caps... Can I drill to use 4 bolt main caps or this block like 318 no has enough material to add more 2 splayed bolts?

How is safe to bore for a N/A Street engine?

Here is a picture of the cast number.

Thanks