Dakota:
I recently installed a pair of Phoenix Gold Octane R5.0 component speaker system in my '00 Screamin' Eagle Roadglide dash. The installation included a pair of 5.25" speakers and a pair of 2 1/8" tweeters. The larger speakers are a direct replacement fit for the stock speakers. The installer had to drill a hole on each side of the dashboard for the tweeters. The tweeters were installed bertween the larger speakers and the fuel guage on the left, and the battery guage on the right.
After the installation, I drove about 30 miles back to my house. WOW, what a difference. I could hear every word of the music in my TourPack mounted CD player. The sound was crisp and clear, and I still had some room left on the volume switch.
The speakers were about $120.00, plus about 2 hours for the installation.
If you need some additional detail about the speakers, you may want to check the Phoenix Gold website on Google.
Hope that help.