The pins/rivets, are going to keep those freeze plugs firmly in place
There is a beauty to machined parts
That is a cool procedure, having just a pair of engine builders at most make your engine, and then they put their name on it. That's pride in the work friends.
Thanks to J Bittle for the open house at his full capability engine building machine shop! It's all in house, nothing farmed out except flex plate grinding. For last summers open house at the Convoy St car shop: http://justacarguy.blogspot.com/search?q=jba+open+house+