Stock wheel is 7" wide… Assuming your offset is unchanged (I don’t think you’ve given that information), then a 10" wheel will be 10"-7" divided by 2, or 1.5" closer to the center of your car. This may or may not interfere with stuff inboard of the wheel, such as a strut, etc. You’ll probably be ok on the rear but the front struts are kind of big and you may see some interference there?!
As for spacers, well, that 10" wide rear will be 1.5" closer to the outside of the car as well (again assuming offset is unchanged). See how things look now, and recognize that you may not have much room to use a spacer and move “outward” without rubbing on the fender lip.