That's exactly what I did. When you spawn the sunburst, look in the parts selector. There should be 2 new engines whose names end with (SBR4 Sounds). The D-Series has 3 new engines whose names end with (Moonhawk Sounds). Did I misinterpret your request?
I just downloaded the file I gave you, cleared my cache, and it worked exactly as you requested. Did you install the 0.10 update?
So, after you put the file in the "Mods" folder, these options don't appear in the "Engine" slot of the parts selector?