Slightly different EFI dual tank question

[Nick_R_23]

So I’m planning on going EFI and keeping dual tanks on my ‘78 K20. My question is, didn’t the fuel neck opening sizes change sometime around 80-81?

Instead of going the typical ‘87 TBI tank and sender route that most do, I’m thinking about buying a new pair of 1978 tanks, and using a pair of Holley drop in EFI modules that utilize the Hydramat system instead of baffles. This would allow me to keep the stock size filler necks and hoses.