ESP32 OTA via sim7600 WITHOUT tinyGSM

I want to use OTA (or least try to) on my ESP32. I use a SIM7600 to connect to the internet. I am not using TinyGSM for reasons that aren't germaine. I use direct AT command and can connect nicely via HTTP Get to my website for other data and can connect to my OTA bin website successfully. I can see the header contains the correct information about my bin file. I am ready to take the next step to update my ESP32.

All of the libraries I have found so far want a client reference to use and process the gathering of the data in their library (from what I can tell).

How can I supply my response from the bin website and finish the OTA process?

use the Update object from the Update library. the Update library is bundled with esp32 arduino core and used in all OTA libraries for esp32