you should be able to just pull it out with due care as Eric says, but the problem may be the rating of your sender vs the rating of the modern gauge - original senders are 30 ohms, and the SW gauge may be intended for a 90 ohm sender, check with an ohmmeter when you get it out, replacement may require a universal 90 ohm sender to make it read right, you'd need to find the specs on the gauge
Bill
