Build sheet decoding

Many of the numbers are the end of a part number like if you have 891 + 892 in the torsion bar section you can go to the proper year parts book and look up torsion bars and look for your car type and the last 3 of the part number. Then the description tells you what it's called.

There are other numbers which represent packages, and you can look in the sales books available on sites like mymopar.com or The 1970 Hamtramck Registry Home Page