Pretty much what Bob suggested but just a little more detail.
The side marker and taillights (running lights) are on the same but different circuit than the turn/brake lights. The
Scamp wire color code is green for the running
light wire. You have a short in your running
light circuit. The most abuse is at the 7 pin plug , I would check this first, remove the green wire and reconnect the plug if it does not blow the fuse then it is a wiring or light bulb issue. Next remove the running and taillight covers and remove the bulbs and check for a short in the fixtures and bulbs then check the wiring with a meter. If there is still a short start tracing out the green wire and check for a shorted wire.
The
Scamp website Owners Manual will give you the 7 pin wiring configuration and the wiring color code.
Eddie