Hi, and welcome! With the 8-lug bolt pattern on the wheels, it's possible your truck has either a 3/4 ton or a 1-ton capacity rating. Does it have single or dual rear wheels? The series number will also help to identify it. I believe a "3600" series chassis is 3/4 ton, and a "3800" will be the 1-ton rating. Our resident tow truck expert is Spanky Hardy, and I'm sure he will chime in soon to correct any errors I've made so far.

If you plan to rebuild any of the missing towing equipment, be sure it's made at least as strong as original, and stronger is usually better. I spent a lot of time doing towing and wreck recovery, including rigs in the 40-ton and up weight range. No matter how strong a tow truck is built, there's an operator out there somewhere who can overload it!
Jerry

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