This was done with an extreme amount of juggling. Prob was well over a 90 min game. By this point the game is slowed to maybe a 5 game seconds to 1 real second due to lag. Maze got a bit messy towards the end. Once the elite guys got near the end, I would do a bit of block/unblock to cycle them back a few mobs. This only works when you have a decent amount of space between them and the rest of the pack.
Key for me seems to be making the longest maze possible which gives me the juggling space.
I also stopped using the EMP pulse once I realized I needed the money elsewhere and that I did more damage if I let them hit more pulse emitter then juggled them back.
I made a few single target towers and focused them on the elite guys 99 perc of the time, with the exception of when I over spent myself and couldnt juggle. At those those times, I killed the lowest mob I could find for some quick cash.