Burning out the bulbs is normally due to the voltage being too high or vibration or maybe the wrong bulb. With the engine running at a high idle and no lights or accessories turned on check the voltage across the battery terminals.

1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy