The 2 holes in the is one are for the oil cooler the es didn't have.
I was waiting to see if anyone else chimed in too be honest, but no one seems to really care about these anymore as people just swap bumpers now
In good condition though these things pop up on ebay for 200-300 bucks. As far as I know I have only ever seen one replica (eurostyle had one) but those have long vanished also.
The oem mounting you need long discontinued brackets, and this crazy bar, I might have them kicking around somewhere as I tried to assemble everything I needed at one point.