Can't switch to Groovy 2.4 on GGTS

I followed the following guide to upgrade to grails 3.0 & Groovy 2.4 But I cannot seem to find where in eclipse (GGTS Version: 3.6.4.RELEASE) I can switch the compiler.

This is the guide I've been following: https://tedvinke.wordpress.com/2015/04/10/grails-3-released-installing-gradle-and-groovy-2-4-support-in-eclipseggts/

Did everything fine until step 5.

Here's the problem:

All I want is to upgrade my project to Grails 3 & groovy 2.4 Is there any other IDE that supports this perhaps?

Thanks!

Found the issue... Just posting this in case someone else gets here.

Apparently the 2.4 compiler did not install correctly as I expected.

The solution was to reinstall Groovy 2.4 Eclipse Feature from this link in eclipse marketplace: http://dist.springsource.org/snapshot/GRECLIPSE/e4.4/