Unfortunately there is no way to get one you'll just have to wing it when you cut the holes. That's what i did. Pretty much just held extension to bumper, made marks with a marker, then but extension aside and cut the holes

 

Just a little info to potentially save some money if you need the attaching hardware. I called the dealership and they wanted $85.00 for 13 spring retainer clips P/N 12493719. I then searched the Web and found shop-supplies.com I got 15 clips and 15 side rocker fasteners for $35.00. Alot cheaper then alot of other sites. It took a week and a half to get them but it was worth the wait since I'm in no rush. Just passing forward some info.

 

I bought them on ebay, very cheap there as well

 

Do you have the diagram got the rocker / sides(like you provided for the front and rear)?
Thank you

 

No, sorry.

The diagrams I found for the front & rear came form GMpartsdirect.com

 

I did find this.... on this forum.... Link ---> https://montecarloforum.com/forum/pa...diagram-42112/

 

The sides are really easy. 7 upper clips and 7 lower clips. They all just pop in basically

 

These are the type of clips for the upper part..

20 Rocker Panel Moulding Clips for GM Avalanche 2002 on Replacement | eBay



And these are the type of clips for the bottom part..
Set of 15 New GM Rocker Panel Molding Clips 10431761 Free Shipping | eBay

 

About to pick up a rear and front extension for my LS friday, any tips on how to install without the vinyl outline?

 

When I did my front bumper I started with the middle tab and worked my way out. I'm made the hole for the tabs a little wide than needed, and I've had no issues since the clips hold it lip on tight. All the holes I cut into the bumper were along the seam on the bottom of the bumper which made things easy. I haven't had to mount the rear so I have no idea.