I wish I had Before/After pics, but I don't ;( At any rate, I did what you said: 1"F, 1-3/8"R lift, spacers only. Definitely moved the rear tires closer to the front of the wheel well. There is more space above and behind now. As
says, you need a subframe spacer kit to move the wheels back into the center of the well - only then do you get more space.
I wasn't trying to run bigger rubber, so didn't matter to me, but figured since I did exactly what you were thinking about, i would chime in.
There is a good video about it ... but my google-foo failed me.
If I were to do it all over again ... I would get the full kit ( spings, spacers, sub frame etc ). do it once, do it right and yes, unfortunately, it isn't as cheap as just some strut spacers.