I have pretty much the right position, but I do not sit really close to my machine. Most of the time my arms are pretty much extended. Works for me.

Raise the height of your sewing table, chest or desk any way you can!!! My sister bought me a set of bed risers at Walmarts to put under my sewing table so MY machine would be at the right height! It worked wonders, no more hunching over. I'm
five feet ten inches tall and I know all about hunching over!

Northwest Arkansas here not borningm love it here

Elenor Burns also said to put erasers under the back of your machine it give it the slight slant that you need.
Haven't tried it yet, but I'm going that way right now.

I had tried twice - 2 different office chairs and I didn't like either for quilting. I use a wooden stool and that puts me where I want to be.