DC Sweep multiple variables at same time

I'd like to run a dc sweep for two variables at the same time. For example, vdc_Var1 would start from 3V to 6V and vdc_Var2 would start from 6V to 3V.

I found a similar post here:Sweeping 2 variables (at a time) in Parametric analysis

But I didn't see the "Group as Parametric Set" option when right click on the global variables.

My ADE XL version: 6.1.5.500.9

Is there any other way to do it?