You should not just elevate the front sight. This will make you shoot low when not using the red dot.
What is the goal? Are you trying to get a co-witness with the iron sights at the same time as running the red dot? This would actually slow down your sight alignment and kind of defeats the point of red dots.
what type of mounting system? Is the slide cut for a red dot plate or is this just a rear sight dove tail mount? Without a rear sight the front is much less useful (practically useless, not totally but…)