Driver side mirror: Color cap?

Hi all,
Have been reading other forum threads and am still a bit confused: JAfter riding with a broken mirror assembly for months, attached with heavy duty tape, just bought and installed new mirror housing and assembly for driver side mirror - part came in black. I may have done this "cart before horse". ***I have a spectra blue Prius, am wondering if I can take the blue color cap from the original mirror and pop that on the new one?*** Or, must I have the new one painted? (ugh). As it stands now, my car's ears are now different colors and it looks awful! Hoping someone can say, yes, the cap comes off the original mechanism (with a little prying) and can be popped onto the new one. Advice appreciated, and second date with local mechanic this afternoon to try to sort!

 

I love it when people tell me what I want to hear! I have been trying to pry the damn cover off --- let's just hope a mechanic has better luck than I do! I can't get it to budge. Thanks for the responses!