Spark plugs?

So I bought a set of spark plugs for my 1970 350ci engine, but when I was middle of changing oil, I've found out that those didn't fit in to my heads. Then I remembered that back in 2009 autumn I had a problem with the heads. There was a tiny crack between cylinders 1 and 3. And the fix was back then just to buy used heads and install them on. So, now I have to find out what heads those are and buy new set of spark plugs to it.

43700 mile maintenance.

43700 miles on odometer. Last oil change was 7900 miles ago or two winters ago. It was about time either way. Jacking up front end. Growl underneath. Position oil gather little bit off set from oil pan plug. Use the force to open oil pan plug. Stand up. Wait. Jack up other side little bit more. Wait. Pick a hammer and screwdriver. Growl underneath again. Strike screwdriver throught the oil filter. Wait. Rotate CCW. Stand up again. Fill the new oil filter. Growl underneath again. Screw that CW to hand tight. Stand up again. Open hood. Open valve cover. Pour 4 liters fresh oil. Close valve cover. Close hood. Easily done.