Pour the 2 boxes of strawberry Jello into a large mixing bowl. Add the boiling water and whisk until the gelatin is dissolved.
Add the cold tequila and stir well.
Pour the mixture into 12 plastic Jello shot cups and chill, uncovered, for 2 hours or until completely set.
Once completely set, dip the rims of each cup into water or corn syrup. Place each cup onto a plate sprinkled with coarse sugar (or margarita salt if you prefer a sweet and salty Jell-O shot ) and coat each rim. Return to the refrigerator for 30 minutes to allow the rims to set.
Before serving, slice the limes into small wedges and place on the rims of each Jello shot cup.
You can make these strawberry margarita Jello shots a few days ahead of time and cover them with the plastic lids that came with the cups. Before serving, remove the lids and coat each rim with sugar (or salt) and a lime wedge.