Not sure what year they started casting 5.7 onto the 350 block. It's on the side by the casting number 25504744 and also above the bellhousing. Also never seen the 4-LINE cast in the bell housing area. Check out the casting flash on the crankshaft. Main cap on the left and rod bolt to the right. This photo was after I broke several pieces off with just my fingers. The heat shield over the LH exhaust manifold has an extension welded to the bottom and looks like it had a heat riser valve. It is flat. Not sure what year this is. Has cap screw rods I will be posting for sale in parts.