How do I group together (mixer view) a few tracks of guitars so I could bring the entire guitar tracks volumes down at certain times at the same time for dynamic mixing? So I don't have to individually ride the faders during a mix or for automation. I would like to have the ability to ride one fader and bring down all 4 tracks at once. Thanks 

Have you considered making a bus track to do the job? Send the output of these guitar tracks to the new bus track. Seems to me the bus track fader would then do just what you are seeking.

Bussing multiple tracks is another option, but if you want to group faders in console view, just select a channel by clicking the very bottom of the strip, then swipe across to add other channels.  Once selected, right click on one of the faders.  there you will see a menu item, Group Faders or similar.  Click New Group, to Group the selected faders together.
 
In console view, you can also use quick group by holding down the control key and moving a control, ie.  Fader, pan, ect.  this will make the same change on all channels of the same type, like midi, audio, ect.   If you select the tracks first, then hold down the control key and change a control, then the changes will be made to just the selected tracks.

Route your guitar tracks to an Aux track