Kirk,
Welcome to the forum. Here you can find an almost endless supply of information about the Shopsmith and it's related tools. You said when you purchased the Mark V it was missing the upper saw guard, power tool woodworking textbook, and the tool rest for the lathe. Since you bought the 520 table and pro-fence system for it hopefully you received the Upper and Lower Blade Guards for it. The tool rest is easy to replace, if you have not done so already. Although the Arm and post vary by Shopsmith Model any Tool Rest from a Mark 5 going back to the 1954 Greenie through today will work. Even the Tool Rest from a Model 10E or 10ER will work. The main difference between the early Tool Rest and today's is the machined indent ring on the Tool Rest's post where the set screw on the arm contacts. The picture below is a Lathe Tool Rest from an early Model 10ER.
If you haven't picked up one yet the book Power Tool Woodworking for Everyone is available for free, in digital format, here on the Shopsmith website. Check it out as it has a lot of good information on using the Shopsmith Tool. The 4th edition has a mix of the 500 and 510 model table systems being used. Earlier editions have only the 500 table system except the 1st edition which was for the Model 10E and 10ER.
If you come up with any question feel free to ask them here.
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