I installed slackpkg twice.
 

Yeah so uh, how do I delete one? I have versions 2.82 and 2.81 installed.

When the dialog comes up uncheck the version you want to keep.

Thanks. First time using slackpkg so sorry if this question had an obvious answer.

No problem, I had a similar problem with two versions of Mesa and libdrm installed, which caused slackpkg not to want to make the usual updates. Was more or less a simple accident that I found out that slackpkg can easily handle such a situation.