Well now i'm just perplexed!
OEM:
Fuel pump ring:
GM Part # 22682111
ACDelco Part # G41
One of these maybe??
Interchange Part Number pump
MU1883, M10229, 67791, 69446, 19207847, 19207848, 19208880, 19208881, 19370390, 19370392
19426300, 19260080, 19256399, 19206830
Seems to be heading in...