Can I use lora32 v2.1 and solder gps myself as the t-beam is 2x as expensive so would gps function and where would I need to solder the pins and what gps would I need to use normal 4pin neo6m or something else

[mart890]

[ae5au]

The wiki documents a bit about how to connect a GPS and the pins can be defined from the web UI:
https://github.com/dl9rdz/rdz_ttgo_sonde/wiki/Hardware-configuration

I have one of these on my build. Not necessarily for any specific reason other than I'd ordered a few for a different project:
https://www.amazon.com/dp/B0B31NRSD2

As far as pins, you only have to have ground, power, and data from GPS. You can optionally add data to GPS and the firmware will try to configure it for you. I don't have mine handy at the moment, but you'll just have to be careful about which pins are used for other things on the board (display, SD card, etc.)