I was placing an order for other stuff and went ahead and bought these;

http://www.classicindustries.com/product/firebird/parts/fb018a.html

What is the correct way to mount these?

Just push em in? Drill small pilot hole? Any adhesive?

They glue on. I don't know the best glue to use but I know what glue not to use. I used the weather stipping adhesive and when it gets hot it slides off. I need to pull them off, clean them up and try again.

I ended up using loctite Super glue - "Ultra Gel Control". Seems to have done the job. Only time will tell.

I've cleaned off the back of the emblem and the door panel with grease oil remover the applied 3M tape worked fine

I've used Amazing Goop for years, and it's never let me down...door panel emblems on for over 6 years and no issues.
Amazing Goop

Which one? This is the route I want to try.

I used Amazing Goop as well.

Shoot, I quoted the wrong person. I want to try the two sided tape as well. Which one did you use?

I used the "Amazing Goop" based on you guys and I'm pretty impressed with it.

Door emblems are nice and tight. Time will tell how they hold up. I'm using the Goop around the house too.