how do you set VTA onthe SME 309 tonearm?

Zd542...SME supplies a special wrench for these screws. These are the correct screws to both move the arm forward and back and up and down.

I was a SME dealer for many years and have owned quite a few different SME arms through the years.

To add to Tom's comments above, the OP never asked about a tool. He asked how to set the VTA of the arm. I bet he already has the wrench. He justed needed to know how to raise and lower the arm post.

Tom even showed him where the screws were in the link he provided, so yeah, this got way over complicated...

Those really aren't meant to be "tamper proof" screws. They are just what SME uses and the tool is included with all the arms. It's not rocket science.