I don’t have a 223 engine apart right now for a head number location; the casting numbers will show up as raised letters and number on the part. The head with the valve cover off it could be in top surface next to valves and or be unbolted from block some of the casting numbers are seen looking up towards the head gaskets deck surface. For an example of a casting number check the block center mass down near the oil pan rail on drivers side. The 223 came out in 54 so with your 58 we might see a 1954 casting up to a B7 or B8 number so head number for a 58 might be B8AE 6015
This decodes B8 = 1958
A = Designed for a full size Ford
E = Engine
6015 = a Block.
A few of common part number these are Fords generic id for engine parts
Engine block 6015 Cylinder head 6090 Intake manifold 9425
Distributor 12127 Camshaft 6250 Crankshaft 6303
Connecting rods 6205
Casting numbers will get you close but don't always tell you the whole story because it is when part was first designed and these parts can be used for many years. When they make a design change (i.e. part has been revised or improved from the original design then a casting number will show that “for example with an A at end” if the part stays the same than casting would just be carried through out several years with same number.
To know what the actual year of the engine head, block, etc. you will need to find the casting date. This date code will also be cast on the block (or Head, Manifold, etc.) it will tell you the exact day when the part was cast. They will consist of numbers and letters for an example 8 E 12 with the first number of 9 being the year; this would then be used with the casting number above for decade and year. D is for month of May, and 12 for the day so would be May 12, 1958.
A = January
B = February
C = March
D = May
E = April
F = June
G = July
H = August
I = September
J = October
K = November
N = December
Hope that helps you some.