Should be a 223, never heard continental get credit. If you go to the Fordsix site you can get some good info. The truck version was a 262 I think but I don't think a straight out interchange on parts, those are fairly uncommon. 1964 was the last year for the 223.
When changing a timing gear, remember the marks don't line up like later engines, they have 12 pins (chain links) between them. Ask me how I know, lol.
Also the head bolt sizes changed somewhere. I put a 60 head on a 63 block once and had to drill out all the holes in the head.
To me the 57-60 is a way nicer and more desirable truck than the 53-56, better looking too except for the 60 and it has an ugly mugg. The best looking one is 57 with the single headlights, then 58 still had the nice hood lines and round turn signals, 59 looked like a 58 but had the uglier hood and square turn signals.
These are very good cabs but the cross brace will rust out, you can pull up the matt and see if it is coming through. Also look at the door/fender gap. If it is starting to be wider at the bottom then you need some attention to the cab mounts. I have actually jacked the cab back in place with a floor jack and put 2x4s on top of the frame to keep the doors out of the fenders, worked good for a couple years.
My ideal truck would be a red/white or turquoise/white 57 big window, short wide with a 312 and 3 speed with overdrive.