Finally got them on the flow bench... In hindsight, there are a few things I wish I had done differently but since this is a budget build and my time to work on projects is few and far between, I'll take them for what they are, at least for now.

Just to recap, these are 452 heads with 2.08 / 1.74 valves, template porting, gasket matched, pushrod pinch opened up a bit and bullet nosed guide boss. They are going on a 413 which is why I retained the stock valves to prevent cylinder wall shrouding. It's also worth noting that these cores came off my work truck with a ton of miles on them. We did install new guides but reused the existing valves. As a result, the intake valves are fairly deep in the heads which is kind of a bummer. I'm sure that if I had replaced the valves and spent a bit more time on the port work, I could have gotten better results. However, I chose my stopping point and this is what I got.

Honestly, I really don't mind porting but if you consider the cost of valves, guides, hardened seats, labor, etc, it makes it really hard to stick with iron heads. That being said, I'm thinking a pair of Sidewinder or Stealth heads will be a better starting point for my future "budget builds"...