Re: Engine Block ID/Stamp Code - 305 or 350?
The 2 areas to look for numbers. The area on the top of the block in front of the passenger side head. The numbers there will be stamped into the deck of the block. They're usually full of dirt, paint etc and very hard to read. Those numbers will tell you the most about the block. They're not under the valve cover or on a tag but stamped into the block.
The casting number is on the engine part of the bellhousing on the driver's side. The casting number could distinguish what bore the block has to know if it's a 305 or a 350 but won't tell much else about the engine. Casting numbers were used over many years and on many engines. ie: an 010 4" bore casting was used for many years for 302, 327 and 350 blocks. Unless the engine has been painted with latex house paint, the casting numbers will still be visible although may have dirt and oil covering them up.
The numbers you want to get are those ones in front of the passenger side head. Those will tell you more about the engine than any other numbers on the block. At least you know it's a 305, not that any 305 is anything special.