Go to the indicated locations, and interact with the yellow icon at Tacos Malos' drive-thru window to speak with Dane Vogel to get each of the three weapon parts for the Last Supper weapon:

1. Travel to the Hellwrought neighborhood in the Forge, and look just west of the highway on-ramps. Tacos Malos is about one block south of the Torment Fraud activity.

2. From the first Tacos Malos location, go north to the Den, and enter Satan's Brilliance. Tacos Malos is just south of the Den's Marshalling Grounds, in the northwest corner of the zone. The Tacos Malos drive-thru window is in the alley; the sign can be seen while following the main road west from Shakespeare's club.

3. In Shantytown, fly to Glutton's End, and look below the highway bridge leading south into Downtown. Tacos Malos is in the lower southwest corner of the neighborhood.