Hi Tim and WELCOME:
That green is called "Vintage Mint Green". They only had that particular green color on 2004 models.
The Deluxe model was sold with 17" 16
spoke wheels that were painted aluminum and did not have a
Hardtop.
The Premium model was sold with heated seats, and
Hardtop choices for the premium (VMG)green car were black, white or green. The Premium wheels were 17" 7 spoke chromed aluminum wheels.
There also was an optional wheel available with the Premium model. It was a 17" 16 spoke micro-machined wheel that looked like the Deluxe models wheel, but you could definitely tell the difference between the painted and machined wheels.
Finally, the standard interior color was black. Or, there was a black accent option. The accent option available was a white color for the shifter knob, top of steering wheel and seat inserts.
If you have these, do you also have the white
Hardtop? A very nice look. I have a friend here in New England that has that combo.
Now to answer your question. Yes you can change the shifter knob, but I believe a TBird knob is around $250-300 if I recall.
I hope this info helps and good luck!!