Detailed coolant fill process?
 

My 2001 Boxster S suffered a busted oil cooler. I replaced with new seals. I got oil in coolant and now I’m flushing system over and over and I’m sure I’m not doing it correctly. I do not have access to air. I’m having to do this on the side of the road. Pouring from drain pan into buckets.

I’ve flushed with Shout once, and now in second go with Blue Devil degreaser.

Can someone please tell me the exact, detailed steps to fill coolant quickly and correctly.

Thanks,
2001 BOXSTER S

From Pelican Parts "How-to" Articles:

...In the trunk, remove the oil cap, lift up the "trap door" panel (Figure 3), and then screw the oil cap back on. Flip up the metal clip that opens the bleeder valve (Figure 4). If you have an automatic transmission car, then you need to remove fuse B1, which is located in the fuse panel near the driver's side foot well (see Photo 5 of Pelican Technical Article: Roof Rack System (Roof Transport System - RTS)). This will disable the ATF cooler shut off valve temporarily. Now, fill the car up with coolant, until the coolant level is visible at the bottom edge of the coolant tank. Start the car and run it at idle, topping off the coolant to the maximum level, until no more coolant can be added. Rev the engine and let it settle down and top it off again if the level decreases. Be sure during the whole process that the car does not exceed 176° F (80° C) while bleeding the system: if the car gets too hot it will interfere with your ability to fill and bleed the system to the proper level.

Now, reinstall the reservoir cap and let the car continue to warm up at about 2500 rpm for 10 minutes or until the thermostat for the front radiators opens up. When the thermostat opens and coolant starts flowing forwards, the electrical radiator fans should turn on. Now allow the car to continue to warm up a bit more, revving the car to about 5000 rpm every 30 seconds or so. Remove the reservoir cap slowly, letting any built up pressure dissipate. There should not be any tremendous pressure built up because the bleeder valve is still open at this time. Top off the coolant in the tank to the maximum level, reinstall the cap, and repeat the process of revving the engine to about 5000 rpm for another five minutes.

Now, allow the engine to idle for a few minutes until you hear the radiator fans cycle on and off at least once. Turn off the engine, and slowly remove the reservoir cap again, relieving any pressure that might have built up there. Top off the coolant until it reaches the MAX level indicated on the coolant tank gauge, located on the side of the tank. Flip down the metal clip to close the bleeder valve and replace the "trap door" panel on top of the tank. If you have an automatic transmission car, then replace fuse B1 in the driver's side door kick panel...

Here's the full article:
https://www.pelicanparts.com/techarticles/Boxster_Tech/29-WATER-Flush/29-WATER-Flush.htm

P.S. It helps to have the back of the car jacked up. And drive it for a few days with the bleeder valve open.

That seems very complicated

Jack up rear, turn on heat full blast, fill coolant, start car and run/rev until it heats up, adding coolant as necessary. Once you get close to operating temp make sure you have sufficient coolant and shut it off. Then just close cap and drive around with vent open a few times and youre good

That's pretty much what I've done to all my boxsters and boxsters I've repaired at the track. At the track you usually only have one chance to do it. I usually jack the back end up so high that the front bumper is touching the ground. Never had a car overheat from doing it that way

Because of the oil contamination this process is a major pain. I’m thinking jacking car up higher is the key so thank you.