This process would likely apply to other Homebrew formula also.
First search for your desired package:
brew search go
You should get a list of results that include the below. Not "go" is very unspecific so you may get a lot of results:
==> Formulae
go ✔
[email protected]
[email protected]
[email protected]
Then install the desired version:
brew install [email protected]
Remember that you can have more than one package installed at the same time, but you cannot have them all available at the same time.
So if you have the latest/generic go
package already installed you need to unlink it first:
brew unlink go
And then you can link a different version:
brew link [email protected]
In some cases you may need to link them with the --force and --overwrite options:
brew link --force --overwrite [email protected]
I think using Go's built in method to manage multiple versions might be less "violent": https://golang.org/doc/manage-install#installing-multiple