If you watch videos of Duane Eddy playing this live, he uses the tremolo arm only occasionally. The story is that for the original recording in 1958, the sound was obtained by placing Eddy's speaker at one end of a large (empty) water tank and the microphone at the other end, and used it as an echo chamber.
A few years ago, I posted my recording of this on this forum, which is also on my PSRTutorial Performers page and my Youtube channel. I would not pretend that I got the sound perfect, and if I was doing it again today I would probably do it a bit differently, but you might want to try my settings as a starting point. These are (for my Tyros 5):-
Voice: Tremolo Guitar (Tyros 5 Legacy voice)
Filters: Harmonic Content +15 (79 on the scale 0-127);
Brightness + 63 (127 on the scale 0-127)
Effects: Modulation 71
Reverb Hall 1 Value 127
Chorus 6 Value 40
EQ: High 40
Low -40
+ modest use of Pitch Bend wheel while playing.
I started in the key of E in the octave below middle C, so you my want to use the transposition function to move the right hand part down an octave while playing.
Regards
Roy