I have a 1998 Ford Ranger XLT 4x4 4.0 V6. I want to replace the standard power port and the cigarette lighter with USB ports. It seems easy enough but I'm wondering if I'll run into any unforeseen problems. Also should I upgrade my alternator to more capacity. The goal is to charge my phone as well as my bicycle headlight.
I don't understand why do you want to do that. Just buy a good quality car charger.
The other thing is that alternator is making so much power that you do not need to change the alternator.
There are simple plugs made that plug into your lighter socket.
Standard alternator will charge both without issues. They are very low amperage chargers.
Lots of them on Amazon...search..."12v plug in usb port"
Check the fuse rating for your cig sockets. For example it may 5A.
5A x 12V = 60 Watts. That is the most amount of power you can use before you start blowing fuses/melting wires. So check your devices (the power is usually printed on the chargers in very tiny text). Some modern tablets can use quite a bit. And leave some margin.
Don't worry about the alternator.
