Hi guys just wanted to share with everyone how I did the serial port jailbreak without soldering.
I used this adapter (DSD TECH SH-U09C2 USB to TTL Adapter Built-in FTDI FT232RL IC for Debugging and Programming) from
https://www.amazon.com/gp/product/B07TXVRQ7V which allows you to easily convert to 1.8v.
I connected the RX and TX to the TX and RX on the kindle by inserting a sewing needle into the dupont cables provided by the adapter and taping them to the board. I also taped the GND to the metal plate.
You can see how I did it in the photos. Hope this helps for people who are not comfortable with soldering!