Keep it at the recommended 50/50. The water does the cooling, the additive is an anti-freeze, anti-boil and lubricant. If you do add water, grab a gallon of distilled water from Walmart. $1.38 well spent.
I went to 265/70R17 with 3/4" level. I don't think it was needed to clear, I just wanted it. That is generally considered the limit. This has been well discussed here. https://www.ranger5g.com/forum/threads/biggest-tires-no-lift.2458/
I would send an email to [email protected] and ask. It does say "This is not a Grille, these are individual “F” “O” “R” “D” letters that overlay on top of the OE Ford Raptor Style Grille". Save the reply in case you have to do a return. :)
My XLT FX4 with Hankook 265/65/R17 tires was 35.5" ground to center of the wheel well arch on the front and 38.5" on the rear. I went up 3/4" in the front and middle of center cap to the same location is now 22 3/8" front, 23 1/2" rear. That should give you a good idea.
I just ran our and measured mine. Mine is leveled 3/4" with Eibach struts and that was right on. 22 3/8 front and 23 1/2 rear. I would have to pull it out of the garage to measure passenger side and I haven't had my coffee yet. :) FWIW, I swore mine was al least 2" higher when I looked at it but...