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Multiple short, minimal steps:
1) I removed the foam and foil insulation from the bottom of the hotbed.
2) I removed the Kapton tape, foam and thermistor from the bottom.
3) I added 2 additional thermistors and 1 Thermocouple to the bottom, placed a small patch of cotton insulation on top of them and placed new Kapton over the multiple layers of cotton (leaving the cotton loose to provide insulation by the many, many air gaps between each and the thermistors), making the whole smaller than the original area the factory cotton and Kapton tape had previously covered (it was 25-42% of the entire bed underside the original had covered). I added 2 more Thermistors and a single K-Type Thermocouple because if the original thermistor ever failed I would otherwise be buried below it all.
4) I reconnected the (original) thermistor to the machine only. I then used my Fluke 88AV multimeter by connecting it to the unconnected power lines on the 1/2 XT60 connector for the hotbed DC power with the XT60 connector to establish which line was positive and which negative and marked the XT60 connector with a Red Sharpie dot on the positive side and a black mark with another Sharpie on the negative side. I then plugged the correct half of one of the XT60 connectors I purchased for the job and gave it the same Black & Red markings. I then removed it and soldered a brand new 14AWG Black and a brand new Red 14 gauge wire to the new XT60 half connector where the colors matched.
5) I connected the other ends of the 2 new wires to the DC side of a brand new Solid State relay I had purchased for the job to the correct 2 DC screws on that relay.
6) I removed the Hotbed Mosfet from the machine (it was no longer necessary and just wasted extra 24V DC power, so with the AC heater it was no longer necessary at all.
7) I connected the White ("Return", "Neutral") wire from the new AC heater to the same on the new 12AWG power cord I had on hand to the wire with the large bladed pin on the plug end and Black (positive) to the smaller pin cable end. My Solid State Relay included a ground plug so I connected the Green wire to it (Black = Positive, White = Return, Green = Ground in North American wiring).. I then moved the shrink tube I had placed before connecting the output wires from the Solid State Relay to the new wall power cables over each, soldered each and used my hot air rework station (it was right beside me, otherwise I would have use my heat gun for it) to shrink each to prevent any contact between each. Then I moved the much larger heat shrink tubing over the 3 new wires, 3 soldered and shrink wrapped wires and the new power cable and shrunk it with my hot air rework station as well. I plugged it all in (new power plug into AC wall outlet, XT60 to my Creality Ender 5's XT60 and powered my Ender 5 up. It showed temperature matching my hot end (so it was functioning correctly), I set the hot bed temp to 120°C (my usual 1st layer ABS hotbed temperature) and timed it while checking it from the top with my Fluke multimeter's Thermocouple sensor and it hit 120°C in 9 seconds both by it's saying so and my Fluke Thermocouple agreeing, so I upped it to 240°C (where Creality's original firmware had the maximum) and 29 seconds later it was there (but it didn't hold it well as I hadn't yet put the insulation back on). I then placed a cork insulator over the bottom and a Silicone cover over both. After that it both hit temperature more quickly and held it far better.
Forgive me if I was overly verbose above. I do so to try and keep questions from being necessary.