Using a food processor, pulse the basil, scallions, almonds and garlic to finely chop. With the machine on, drizzle in the EVOO; process just until blended. Season with salt and pepper, pulsing to mix. (The pesto can be made 1 day ahead. Transfer to a glass jar, pour a little EVOO on top, cover and refrigerate.)
Preheat a grill to 500 degrees . Place a heatproof skillet on the grill; add the sausage and cook until browned and cooked through, crumbling with a fork, about 5 minutes. Remove from the heat. Place the bell peppers until charred in spots, turning with tongs, about 5 minutes. Transfer the grilled peppers to a cutting board and slice into 1/3-inch-wide strips.
Lower the heat on one side of the grill to low. Oil the grate on that side of the grill. Move the shaped dough to the grill. Lower the edge of the dough onto the oiled grill, draping the dough perpendicular to the grate. For 9-inch pizzas, grill 2 crusts at a time. For 3- to 4-inch pizzas, brill 8 crusts at a time.
Cover the grill and cook until the crusts begin to bubble and brown, about 3 minutes. Loosen the crusts with a metal spatula; cover and cook for 1 minute more. Flip the crusts over; cook until beginning to brown on the bottom, about 2 minutes.
Working in batches, invert the crusts flat side down onto a baking sheet. Spread with the pesto. Divide the sausage and peppers among the crusts. Place the baking sheet on the cooler side of the grill. Cover the grill and cook until the crusts are crisp on the boom and the toppings are hot, 2 to 3 minutes.