Couple questions sorry I'm a noob

have a muffler with 2.5 inlet I believe the sc stock inlet is 2.25 can I weld the muffler on or do I need the pipe adapter ?

do I really need exhaust hangers? Shop want to overcharge

should I use clamps instead ? Cops are *******s around here, I can switch back to stock just in case lol

when i turn my headlights on I can't see my dash or anything but when I turn the headlights off everything lights up again ? Might be a fuse? Can't see how fast I'm going at night lol

 

There is adjustment roller on the left side of your dash. Try to roll it fully to the right. Lights should light up, if not needs further investigation.

 

Exhaust clamps don't work, I would recommend having a flange welded on and bolting the new mufflers.This will allow you to bolt on another set of pipes if need be.
I've had a pipe shoot off my motorcycle that was connected with only a clamp...
I would definitely use exhaust hangers if you are concerned at all about noises in the cabin of your car.

 

Exhaust hangers for sure. The mufflers are too heavy to just hang there and they will hang down and look dumb.

 

Correct. Dash lights are always on, but when you turn the headlights on it redirects the voltage through a section of the dimmer module that drops the voltage. If you turn it all the way until it clicks full on it skips the dimmer section so if it still doesnt work you're going to need a volt meter and the diagrams i posted ten years ago you should be able to find in search to trace the circuit.