
So having those completed first makes the solution below work for you. Again, COMPLETE ALL PERKS BEFORE STARTING YOUR SECOND PLAY THROUGH! Because on 999 mode, Perks do NOT progress. On 999 mode, you start with 999 health, unlimited ammo, on Uber mode, and ALL YOUR PERKS as well as all your weapon upgrades (rockets on assault rifles, super powerful laser, etc) if you completed them BEFORE playing your second run through! I literally just attempted the game last night and finished it moments ago in around 5 to 6 hours total run through on Uber via 999 mode. It feels like playing the game on the easiest difficulty again.

You can replay the entire game on 999 mode and it makes it so much easier.

If you just save this achievement and the Uber Hero achievement for last on your list to collect. Here is a new solution, and in my opinion a better one, it is not faster, but it's much easier to handle (not sure if anyone has mentioned this).
