THIS GUIDE IS NOT EXHAUSTIVE (I didn't record everything, but it does give you useful bits, where you'll be able to get the achievement in one or two tries. It's just helpful as a reference)

The concept to the rush mode is counter intuitive.
The basic idea is this: Fulfil the quest to get the gingers, use the gingers to pop the gold gordos, then bash the gold slimes that come out with carrots or whatever. This gets you roughly 21 gold plorts for each gold gordo. If you do this for the five gold gordos I listed here, you will have most of what you need.

Additionally, you get extra points for bringing in a bunch of each type of plort, but you need to sell like about 30 I believe to unlock that for the extra points. So, while it's pretty much a waste of time to farm anything other than rocky/tabbys, rad/booms, and honey/hunters, you need to also get enough phosphor, pink, and hopefully other types, so you can unlock those for the bonus.

I should also mention, I did this on my second try, and for my first try I had no idea what I was doing (didn't look anything up, didn't know where anything was). It's not difficult, but it's handy to know where things are, and to have a little direction.

GETTING STARTED
When starting, you should be able to fulfil the quest basically right away. If not, just start over until you get an easy first quest (this makes a HUGE difference).
After finishing your first quest, you can complete the first gold gordo just north of the ranch (shoot carrots and junk at the gold slimes that emerge, you should easily get 20+ gold plorts).
You can use this money to make your ranch. Make an upgraded garden for each upgraded corral.
While waiting for the next day so you can do your next gold gordo, go grab a ton of rocky and tabby slimes, and some beets. When you get back to the ranch, make them into largos, and put your beets into your gardens (I did two gardens and two corrals).
Then you need to get at least two keys, which you can use to rush to the mossy area and indigo mine quite quickly (needing only 1 key each), which means you can have rad/boom and hunter/honey largos in your ranch, very quickly (even day 1).
Use the information below to find the right teleporters to help you move around, the right places to get keys, and where to find your gold gordos.

GOLD GORDOS
These gold gordos take three gingers to blow, then just throw junk at the gold slimes to pop them. Do NOT feed them ginger, because you need that ginger to pop more gold gordos.
- Just north of ranch, very close.
- Big island to the west you teleport to has THREE gold gordos.
- North part of the mossy area, by tree roots (it's in the under portion).

SKIPS
- Bottom right of the thin lake above Dry Reef.
Get on top, then fly north to the Indigo Mine.
- You can also keep going, and get even further into the area, where you can get rads and booms.

KEY GORDOS
These gordos take 25 units to explode, so plan accordingly.
- Pink = North then little island to west.
- Pink = Big island to the west, have to teleport there.
- Phosphor = North west Dry Reef in cave below.
- Honey = South west mossy area, just south of the small mountain.

TELEPORTER GORDOS
These teleporters end up being crucial for getting further, and saving you time.
These slimes only take one unit, so just grab something it'll eat and you're fine.
- Tabby = West path out of ranch, takes you to the big western island.
- Rocky = Indigo mine area, the teleporter you take from the east part of your ranch outside the mine.
- Tabby = Top left Dry Reef, in the hole before the path to the mossy area.

DOOR TO UNLOCK
In the west there's the path to the mossy area. That door is quite good, because you can basically just run right to it the moment you get a key, and bam, you're getting hunters and honeys.

DOOR TO IGNORE
West path Dry Reef
You can just go north out of the ranch, then go west. It completely bypasses the westernmost door in the Dry Reef.

MY WINNING RUN
You will notice you do NOT need 75k "in hand" to win. I have less than 60k, and I still got it. I got this on my second run, and my first was terrible (I had no idea where anything was, or even what I was supposed to do. I even wasted a few gingers).