My friend Franklin designed this model using MS 3D Builder. He needed a Garmin to RAM 1" mount to replace a mount that was stolen. He used parts of the things below in order to put together his mount. It says "Iowa made" on the side in Chinese, a tweak to my username HechoEnIowa which means Made in Iowa in Spanish. The designer, Franklin, is Chinese-American.
The Garmin ball may be slightly too small, so it may be necessary to scale up a little tiny bit, then sand the Garmin ball down.
https://www.thingiverse.com/thing:2623766
https://www.thingiverse.com/thing:1535985