99 Ford ranger XLT base model. Park lights, dash lights, and license plates lights out

I checked online and realized it was probably a fuse which it is. Fuse 11 in my power distribution box. The problem is I keep replacing at and soon as I turn on my lights it blows instantly. Have replaced it multiple times. So then I looked under my truck and disconnected the wiring to my taillights and replaced the fuse, it worked it didn't blow. Dash lights and license plates lights were on so I figured some where there's a problem with the brake lights. Any suggestions?

Truck makes clicking/rattling noise when in 4X4?

I have to use an old '97 Ford Ranger with an auto tranny and auto locking hubs at my workplace. When you turn the electronic switch to 4X4 low or high and accelerate it makes a harsh rattling/clicking noise but the truck will still move. Does this mean the transfer case is shot and I will have to live with 2 wheel drive? Since I sometimes have to drive on grass trails it would be nice to get this thing fixed if it's a simple fix.

Is it worth it to upgrade my ignition system?

So I'm wanting some more power out of my 99 ford ranger. I know that one can get a better coil pack and hotter spark plugs to increase performance. But there are also a lot of other details that need to be considered. Like how hot my spark needs to be can be determined by the fuel mixture and how fast it is exhausted and all that. Then the possibility of it not being good on the engine to have that extra energy delivered to it. I was wanting to find a coil pack that had a high output along with maybe some e3 spark plugs to obtain more power/energy/performance than what my stock set up can do. But I didn't want to get one that wouldn't really do anything because I know that my truck has what it needs to run well, bc it needs a certain voltage/power deliverance and it is most likely getting that. I just didn't know if it could work with more. I also didn't want to do any damage with an upgrade. Please share your knowledge and advice with me. And can you recommend any products/setups/upgrades that will be good.