Silicone adhesive should work fine, but my favorite glue for most automotive jobs is Pit Crew's Choice by Loctite. It goes on white but dries clear and does not yellow appreciably in sunlight. I have even used it to seal cracked plastic headlight lenses with good results.
It holds well and remains slightly pliable, so it tolerates differential expansion by parts, which is what you will have with this emblem.
It takes a LOT longer to cure than the tube instructions indicate. Be prepared to keep the parts clamped together for 24 hours if you use it.