I also put a Spectra efi tank on my 74 Challenger. Before I installed the tank, I made a half hearted attempt to remove the sending unit / pump assembly. I didn't readily see a way to get it out unless I drilled out a couple of rivets so I just sealed it back up and put it in the car.
It seems to have roughly ten gallons in it when the gauge reads one quarter.
I don't know how different the Coronet tank is from the Challenger tank, but I would like to hear how you removed yours.
74 Challenger, bought it new. In 1978 I replaced the original 318 with a 446 and 727. Mild cam, Jardine headers, and Holley Sniper EFI.
New engine! 511" RB, Edelbrock Performer RPM heads, Eagle rotating assy, Comp hyd roller cam, Doug's 2" headers.
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