on thins carb, you have a "turnbuckle' and it has 7/16" lock nuts, this turnbuckle is a flow mixture adjustment. you will have to find the correct area that allows the truck to start and run , then do fine adjustment to get it just correct. I would suggest that you either get a very "seasoned" {read as "old timer who remembers these"} service tech, or consider updating to a newer machine or at least a newer style of LPG system.
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