Personally, I don't care for remote needle valves. I've only been bit by a prop once, it was when I was a teenager and I was NOT adjusting a needle valve at the time. Like CGR said, the new OS engines have the HSN slanted back and I think that's the best method. The next best thing is to keep in mind at all times hat your fingers are dangerously close to that spinning prop!

Never reach around an engine.

Walk around to the back side of the prop and approach the HSN slowly and carefully from the rear - And again, remember where the prop and your fingers are!