I managed to install a CB radio in my 2003 Sierra in that useless cubby that normally houses the electronic 4x4 shifter left of the steering wheel. But the wimpy ...

I managed to install a CB radio in my 2003 Sierra in that useless cubby that normally houses the electronic 4x4 shifter left of the steering wheel. But the wimpy speaker is now covered by the dash, actually I ripped it off while I was tinkering with the fog light switch (another issue Im trying to deal with).

So what I want to know is, do I need to buy an external speaker or can I connect the CB radios speaker wires and run them to my door panel speaker or even to my radio?

you can but from what your saying the cb radio might not be strong enough to sound loud. most 2 way and cb radios use 8 ohm and low wattage

You might be able to tap off of one of the speakers in the truck.

I run a small external speaker. That is stuck under my console.

I've seen the external speakers. They run about 15 watts and seem pretty small to be concealed somewhere. How does yours wire up to the cb?

I'm not using one design for a cb radio per say.

It's a Sony speaker made for phones and mp3 players. It was part of a set, one had batteries in it and the other ran from that one.

Both plugged in using regular audio Jacks (3.5mm I think).

So I just took the one that doesn't have the batteries and plugged it into the cb. My cb has 2 ports on the back. One for a PA speaker and the other for a external speaker. Both are the same audio jack.

I find its plenty loud and clear.