Bath tub waste & overflow drain installation.

I purchased a drain like the one in the link below and it only came with a part diagram. Does anyone know the proper methods and sequence for it's installation? Does anyone know where I can find a set of installation instructions? I also would like to know if the washer at the drain's elbow goes at the top of the tub or at the bottom. I have an old cast iron tub with a 2" drain opening. Thanks in advance.

https://terrylove.com/pdf/pp_19-020.pdf

IT goes together just like the drawing shows and ALL gaskets go behind or under the tub. NONE go inside the tub. The installation should be so intuitive that I don't know anywhere to find a step by step procedure. Which is also why the only send a parts breakdown. Put the drain in the bottom of the tub, the overflow at the upper opening, and then do whatever is necessary to connect them to the drain tee.