if you are going to lower it get that done first, you will notice the wheels sit in more from the fenders after. If you do get spacers only get bolt on spacers not the shims that sandwich on your factory length wheel studs.
Problem with wheel spacers depends on the factory wheel, are the pockets BETWEEN the lug nut holes at the back of the wheel deep enough if they even have any? IF your factory lug nuts protrude through the spacers, more of a problem on thin spacers, they might contact the wheel hub and your wheel may loosen off or not seat at all which is dangerous.
If the factory wheels do have the pockets you would need to inspect the clearance first by placing one onto the vehicle NOT using the factory lug nut holes but in between so the wheel studs sit inside the wheels pockets and measure the distance from the brake rotor to the back of the wheel mounting surface. You would then find a spacer at least that thickness plus about 1/8"- 1/4" for clearance assuming the the tire wont rub the fender. Last resort is cutting the factory whel studs shorter.
There should be a few posts regarding what spacers work for what year but I would still double check the measurements or have a shop purchase and install them for you.