Grate some lemon zest into the oil - bring it up to the point you see the surface of the oil "shimmer" - cut the heat off, put a lid on the pot, and let it steep for about 30-45 minutes (until cooled off to room temp). You will then have lemon flavored oil. Use that to brush on your 'tater slices - forget the lemon juice! You could then sprinkle with pepper before baking or immediately after removing from the oven.
Or - after brushing with oil, and before baking - sprinkle the 'tater slices with some "lemon pepper" - or immediately after removing from the oven.
That's a couple of ideas ....
"It ain't what you don't know that gets you in trouble. It's what you know for sure that just ain't so." - Mark Twain