Jim;
Have you the handset for this particular truck that you can monitor the the HEGO (Heated Exhaust Gas Oxygen) sensor?
Are there any DTC (Diagnostic Trouble Codes) showing on the Instrument Dash? Have you taught in the throttle position and the accelerator position sensor? Does the engine replacement have the speed sprocket? Haye you reinstalled all of the fuel system vaccumn lines between the LPR (Low Pressure Regulato) and the mixer? With the handset you should be able to the inputs of the sensor to the ECM (Engine Control Module) and the Module outputs to the actuators. Important item to note spark plugs need to be LPG (R46TS).
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