3 Prong Sending Unit
 

Hello, I just bought an 84 Lindy Skyline built on an Econoline 350 chasis. The beast has 2 tanks and I dropped the main tank to clean it out and I need to replace the sending unit. It is a 22-gal tank but the problem is that every part I pull up for the year has only one prong on the sending unit. My old unit has three. How do I find this old part or how do I convert it to use one prong?

Also, the fuel pump was recently upgraded from mechanical to electrical.

Any help would greatly be appreciated.