Was looking at the protector as well. How difficult was the installation?
It was not difficult, but SOS did the install. Here are my recommendations:
1. make sure the car is raised so you can work on it with plenty of room.
2. you can use painter's tape to tape the bottom piece to the bottom of the car, then measure twice, drill once for the screw holes. Careful measurement, marking is key, so you drill in the right locations.
3. remove all of the screws on the bottom (there's like 13 of them), and insert the top plate onto top of the bumper from the inside, align the bottom piece (a small screwdriver helps to align the holes if needed), then screw in the screws into the metal screw grommets that you put into the top piece. A small dremmel helps to slightly adjust the holes on the top inner piece (take it out first!) of the bumper guard if the metal screw grommets don't fit perfectly on the first try. You only need to dremmel a few holes if the metal grommet doesn't align exactly.
So it takes a little bit of patience, but easily doable. You also get to see how someone rushed on the build of the NSX, as the factory screws / bolts are not lined up perfectly between the different layers, and someone just forced the factory screw / bolt through to make it work. It's not horrible but even the factory can't get it aligned perfectly, lol.
This adds good rigidity to that flimsy bottom portion of the bumper, and provides excellent protection to that naked painted bottom lip. I don't have the carbon fiber exterior package, so I only installed the bumper guards on the left and right sides, but left the center piece naked. SOS said the center black lip portion is cheap to replace if it ever gets damaged, like $200 or so, but the side pieces are what concern me the most, as they are painted, naked, and far more complicated to remove, repaint, and repair. And most of the time you'd risk scraping the side pieces going up / down driveways, steep approaches, etc., and it would be very visible if damaged.
However, if someone has a carbon fiber interior, it's vital to get that center piece protected as well...as that can be a costly part to replace if it's scraped. I feel a ton better having the guards, but I still plan to get the iLift kit because I want to be free to take my NSX to most places without worry.
Your new one is lower than your lowered '91? I have yet to receive my new one but when I test drove it, it seemed to have better clearance than my lowered '91.
Yes, if you look carefully at the bottom of the NSX, you will see that it curves down on the sides at a very subtle angle. So the middle is a bit more clearance, and then it has a very subtle curve at the sides going down, to accommodate the shape of the side bumpers that are lower than the center part of the bumper. The side area is most prone to scrapes as you tend to approach inclines / valleys at an angle...so that makes it even more crazy how it's designed. It looks great but is so vulnerable to scratches and scrapes.
I was shocked at how easy it was to scrape that rubber strip beneath the bumper...so grateful I didn't scrape my painted bumper...I would have been ticked if that happened!! That would have meant removal of the the side bumpers, having it repainted (matching certain factory paints is not easy, plus it's no longer factory clear coat & paint any more), and then reinstalling, waiting 30 days to re-applying clear bra, etc, a huge unnecessary pain and expense!! The bumper guards are vital, and should have been designed as such from the factory!! I predict 99% of unprotected NSX bumpers will have scrapes like this...and it will be painful to see. SOS said they haven't seen an unprotected NSX without any scrapes. I took my NSX to SOS within the first 100 miles to get the bumper guards installed, so mine was one of the first that is still fresh and have not been scraped yet...whew.