I don't have that kit, and I'm looking at tiny pics on my cell phone, but that looks like a Chrysler hemi with holes for the spark plug wires. I would guess its a '50s 331/354/392 hemi. Maybe even a Red Ram hemi of smaller displacement.
All engines with a hemispherical combustion chamber have their intake and exhaust valves located to the sides of said chamber, with the sparkplug at the very center. This allows for the flow of intake gasses into one side of the combustion chamber, with exhaust gasses going out of the other side. It's the most efficient internal combustion engine layout--used since the introduction of the first serious DOHC engine from Peugeot in 1913.
If one looks at any Chrysler Hemi, 1951-58, one will notice a raised stamped steel cover down the middle of each valve cover. That is a wire loom, itself rather common on earlier OHV V8's, for the purpose of aligning plug wires, and often hiding them from view. Take that steel loom or cover off, and you can see four individual tubes in each valve cover, having a flange at the bottom, using a gasket to keep oil from getting to the plugs. The second generation Hemi's (1964-71) never had the loom, or cover, so those holes are highly visible, although Chrysler did install neoprene rubber covers for each plug hole, to keep dirt and moisture out.
Art