I know for a fact that in my 03 montero sport i have 2 under the dash speakers. 2 front tweeters and then the two front door speakers and two back door speakers. But how and the hell am i suppose to be able to know the size without having to remove them? Any ideas?

 

Try looking on Clutchfield site

 

Crutchfield. It asks if you do or don't have the Infinity speaker system. https://www.crutchfield.com/ymm/2003...s-Stereos.html