I think you could glue the base and then attach if you use a lot of alcohol. So you would put the glue on, let it dry to tacky, then spray the inside of the base generously with alcohol, and also spray your head generously with alcohol, before applying the piece. The alcohol would delay the onset of adhesion, and give you enough time to get the piece into perfect position.
If you try this, be sure to wear a sweatband to stop the alcohol getting in your eyes.
Do you mean you don't want to put glue on your scalp at all? That could be a little tricky but is possible as Noah describes above.
If you're only talking about the hairline then life becomes easier. So you would glue most of the scalp as usual, but don't put any glue in the front inch or so. Then stick the UTS on so that it's stuck on solid, except of course at the front inch or so (hairline). Flip up the hairline and then you can put glue on the UTS instead of your scalp.
I do this method quite a lot because the hairline always needs that extra special attention. I have never put glue only on the UTS, because I imagine the hold won't be as good. I do quite often put glue on my scalp (talking about the hairline) and the UTS, which ensures that I get glue right up to the very edge of the base.