Offroad lights on roof racks.

[cico7]

I have 4 sets of lights. 1st shorted and the second one just did't like me I guess.

What you need are the large relays (solenoids) like we use in cop car builds. Here's an example:
http://www.oznium.com/relay80
The material is bakelite and doesn't melt.

Another reason for massive relays beyond what you think are needed is high wattage bulbs have a huge start up current. Otherwise known as "cold filament surge." Your 100 watt lights may draw about 8 amps ..... Running a 100 watt light with the usual Bosch relay is the contacts will weld themselves due to the starting surge.

I have 4 150 watt lights on top.They are split into 2 sets.
Adondo, Thanks for link on the heavier relay...I will look into this.