Here's what I was able to snap a photo of this morning. This is on the #4 main cap (counting from the front), both sides (passenger/driver) coming out of the bolt hole and extending up into the webbing towards the top of the block. Sorry the shots are a little blurry. They looked good at full size on the phone.
My block is the first one, there is a block that is at the machine shop, but owned by a customer who has left it there for over a year that is the second number.
Casting Number Size Year Main Bolts 3892657 327 67 2 3782870 327 62-67 2
Second block is supposed to be still at standard bore, but needs to be bored. Machine shop will be calling the customer today to see if he would be willing to sell it. We'll see what happens there.