New episode of " What's this Part"

RAT ROD AL said

But they don't seem to bolt to a big block. I'll check again.

Click to expand...

The side with two bolt holes "wraps around" the front of the block and bolts to the very front of the block. The block must have the drilled and threaded bosses in front. Not all of them do. The side with one bolt hole bolts to what would be the front hole on the side of the block.
Like this: