OK, I took about 30 shots of my block this morning, both sides, and set this page up for you. They're all thumbnailed and hi-res, so just keep clicking on them to get the hi-res detail. The verdict on the driver's side is that there are
three ribs by the motor mount and
two ribs at the back of the block. Here you go:
http://208.255.159.239/428block/index.html