Ok so I am using the SDonate plugin, the paid version.

When a player buys a kit I want it to assign the permission for kits.roughneck, by steam id. What would that command line be?

oxide.grant user steamid kits.roughneck  ??

Can't seem to get it to work.

Nevermind, after digging through some old oxide posts I figured it out. I was trying to assign the permission to each user. You have to add the user based off steamid to the group that HAS the permission.