More specifically for Mustangs 96-98.. But i'm sure its easily adaptable to any other grilles that have similar mounting emblems.
I love batman so i chose the logo for my grille but you're only limited to your creative skill as far as what you decide to replace your pony with.
There are many ways this could have been done but i was limited on tools, knowledge, and how it was going to work in the first place..
Basically you'll need :
A sheet of aluminum(or sheet metal though i'm not sure how much easier it is to work with) You can buy one at Home Depot, Builder Square, Lowes, Ace etc...
Assorted files to sand down the grooves and corners
A vice to hold the sheet in
A jigsaw with metal blades
Coping Saw to get into the hard to reach places..Safety glasses cause the shavings will get everywhere..
Epoxy for metal, plastic, aluminum...
A marker and ruler..
Metal polish to make it shine
Patience and elbow grease!!
Step 1: Removal..
Step 2: Template
I'd take a pencil and sketch it first before you go at it with a permanent marker like i did... oops
Step 3: Elbow Grease..
Then take your coping saw and get in as close as possible. Then take your files and sand down to the lines you sketched on the sheet. Try and be steady handed as you can.
Step 4: SHINY!!
I used Mother's Mag And Aluminum Polish and gave it about 3 coats. The more you do it... the more it'll shine.
Step 5: This Part Is Tricky..
Carefully place the flathead screwdriver between the horse and bracket right on the spot where it looks riveted. It should come off and just hammer flat the bracket for remounting.
Step 6: Mounting It Back on to the Bracket
Adhere them and aim to get your design as centered as possible to keep it from looking odd when you remount it.
My design was rushed so i didnt clean up my batman logo enough but i figured i can always remove it and sand it down some more as can you.
Step 7: Remount and ENJOY!!
Hope this wasn't too confusing cause trying to figure out how to do it was.. :P