Grilled Shrimp Tostadas with Guacamole and Red Cabbage Slaw

Name: Grilled Shrimp Tostadas with Guacamole and Red Cabbage Slaw
Ingredients: 8 6 corn tortillas; Canola oil or cooking spray; 3 ripe avocados, diced; 1 small shallot, minced; 7 tbsp. lime juice, divided; 3 tbsp. freshly chopped cilantro; kosher salt; 2 tsp. cumin; 1/2 tsp. cayenne; 1/4 c. extra-virgin olive oil, divided; 24 medium shrimp, peeled and deveined; Freshly ground black pepper; 1/4 c. finely shredded red cabbage; 3/4 c. finely shredded carrots (1 large carrot); Cilantro leaves, for serving; Lime wedges, for serving