currently only works with the fork of ProcessJSONInstaller: https://github.com/owzim/ProcessJSONInstaller

install the fork from your processwire installation directory:

$ cd site/modules
$ git clone https://github.com/owzim/ProcessJSONInstaller

install the module from the Modules Page

grab the JSON files from this repo:

$ cd site
$ git clone https://github.com/processwire-recipes/json-installer-modules

in admin go to Setup > JSON Installer

A tab named PWR should be there, install ProcessWire Recipes which will install all the JSON sub modules

ATTENTION: currently some ASMSelects are not assigned properly after first installation, so install it twice (fix on the way)