v-6 had lower intake gasket issues. Could be blown head or intake gasket or cracked head or freeze plugs. On the bright side there is heater core hose's running to the firewall front front of engine and both are toward the pasenger side of engine, check them out. Is the leak above or below the head or toward the back of the engine or dripping on the engine ect. do some looking around it and let me know. The fuel smell in reservoir is a blown intake or head gasket symptom. There are some test you can perform like compression leak down test or exhaust in coolant test but sorry to say you will have to pull the upper & lower intake off to see if lower intake gasket is damaged or not and if not continue to the head gaskets. Unless it runs good otherwise it would be wise to get he heads rebuilt and checked out if you have them taken off. There is basically no way for petro smell to be in coolant without a bad gasket or crack to head.