I spent hours researching this over the last day, only to find that it's really hard to find what we should be doing TODAY. Had my radio act stupid yesterday morning, immediately ordered SD cards after research, and got it fixed today after work.
So, as of today, here it is for W4500NEX:
1. Buy SD card(s). I bought these: https://www.amazon.com/dp/B09CKFWP6N
2. Download the image:
Compressed (fastest download): https://drive.google.com/file/d/1-J9GN8cGtTwOvS_w0AEtBM9lReHBUrA8/view?usp=sharing
or
https://mega.nz/file/P4xCES6a#HM_DyeRdGmWY1wuN1TqyPoR8TyZrJN823oilXAoS-Qw
or