I built Safety Raiser myself. It took me a few tries, but it came out fine.
The only consideration when starting with a project is: The height of your tonearm! This is crucial as Safety Raiser should be able to pass under your tonearm in order to lift it at the end of the record.
The way you make your own Safety Raiser is:
1. Find cueing assembly from any manual TT.
2. Remove cueing assembly from the plastic/metal housing of TT.
you will end up with cylinder, piston with black plastic "tonearm rest", cueing lever and inner metal spring.
All you have to do is:
Remove the little screw on top of "plastic tonearm rest", pull the piston out, put the spring on the piston and insert piston back into the cylinder.
Now you have a tonearm cueing assembly that does exactly opposite of what it used to do: It is now when depressed, starts to rise slowly out of the cylinder.
That was easy.
Now you have to figure out the metal wire trigger and the appropriate height of the whole Safety Raiser.