If it popped the air filter I would be inclined to think that the conversion is a simple mixer type that simply dumps the gas into the inlet manifold before it splits to go to each bank of cylinders. Depending on when the conversion was done this could have been the only practical way to do it. Fortunately systems have improved these days so even my 1992 model Ram has gas injection alongside the petrol injection to prevent a build up of unburnt gas in the manifold.
You can either service the system yourself or take it to a local expert. Your vehicle, your money, your choice. Assuming I'm right about the type of system you might want it upgrading to the latest and best. Click here
for local fitters.