Adjusting / controlling / moving an objects vertex groups using geometry nodes

Question

I have an object that has a vertex group that I use to adjusts it's size to exact dimensions (see animation below)

I would like to do the same thing using geometry nodes. I was thinking of accessing the vertex group and using a transform node to move it along the Y-axis. How does one access vertex groups using geometry nodes to do this?

Example: Object needs to be 5.5mm (blend file attached)

My thought process:
1) Get current dimensions of object (2.0mm)
2) Add or subtract current dimensions from the desired dimensions (5.5 - 2 =3.5mm)
3) Get vertex group and use a transform node to increase it by 3.5mm along the Y-axis

The goal is to do this in / using geometry nodes

Answer 1

Make a new input and plug it into Selection in a Set Position node. Press N to bring up the right panel, go to Group and change the Type from Boolean to Float.

In the modifier tab, click on the spreadsheet icon to allow the input of an attribute. Enter the name of your vertex group. In my case, my vertex group is named "SideGroup".

Now you can use the groups input as a vertex group selection. You can view all the vertex group weights in the Vertex portion of the Spreadsheet area.