1999 Chevrolet Astro windshield wipers quit

The picture you describe sounds like a comedy act but we are sure it is not funny to you. When a conversion is done, the wiring must be integrated to the added conversion. In doing so, something has apparently gotten loose and is shorting out. You might want to look and see if there is a storage compartment that has a light that comes on when the door is opened. If there is, there may be a bad switch in that compartment. Otherwise, all we can tell you is to start checking wires and connections.