Sorry, I thought I read you still had 4.5"BS.
Jacking it up is a start, but if you can find somewhere to flex it up, it'll give you a better test. Roadside ditch, sloped loading dock, something.
If it turns out you do need them, spacers aren't as bad as they used to be. Gotta make sure you keep em torqued right, and check them occasionally. Pretty common solution for putting the narrower 8.8 in the TJ and XJ.
And doing stuff "right the first time" only means you were lucky! Experience is the best way to learn!
Robert