[PontGuy]

I didn't mean to take over as the resident expert here, others that are watching along please jump in (and let us know if you disagree!)

The numbers look fine. Maybe a bit lower than optimum but you should have no problem with pump gas. I would have been much more concerned if they were very high. And readings are pretty consistent between cylinders. The carb not being locked open shouldn't have made much of a difference. My bet is that the engine should run good once you get past tuning.

If those are 061 heads then my guess is that it has dished pistons, or a very long duration cam. Or something else was done to get compression down. But all we can do is guess for now.

Next step is to get the timing right since timing can affect the vacuum reading if it is way off.

The goal should be to get all-in timing around 34-36 deg. Depending on the weights/springs in the distributor and assuming it is working right you may get anywhere from around 8 to maybe 16 deg at idle with all-in adjusted in 34-36 range. If not then you can add distributor advance curve work to your to-do list.

Hoping that you have adjusted timing before so know the drill. If you are not sure how to do it then ask questions!

This is fun stuff- wish I was there!

Yes the plug does look kind of ugly, but not sure how much you have run it at idle and how far off things are. Plug reading is definitely not an area of expertise for me.