PM ConeDodger here on 914world, he has the manual on CD I believe.
Like other said rust is a big concern with these cars and it hides , rusting the longs and rt suspension console from the inside out, hides under the tar on the floors and any other crevice or corner water can collect.
Look for rodent chewed wiring before you power up.
Flush out the fuel tank and lines, change the oil, charge the battery.
When you put oil in the cylinders use something light weight.
If you can find it, I use Swepco 503 Fuel Additive, it is oil based and thin so it penetrates and still lubes, also burns off without fouling plugs.
If it is still fuel injected it will need all new fuel hose due to the old hose won't hold the fuel pressure in a fuel injection system. You may want to look into stainless steel fuel lines through the tunnel when you get nearer driving or running much. The plastic lines deteriorate and fail leaking fuel inside the car.
Good Luck
Jim