Stop in for a cup of coffee

So, I more of less calibrated my NOS fuel gauge with a more or less correct new fuel sending unit. For a A100. Put new gauge in, and it showed empty. So far I have pumped 6 gallons out. Need more fuel cans. Waiting on them. So the "Right" fuel sending unit is real crap!! The ones they sell for the A body.....I am going to put a gallon back in at a time, after pumping it all out, and note gauge readings....After I install new sending unit...From A 100 Van....
So. Pumped till there was no more. I used the cars electric pump to empty. Gauge showed empty. Got 8 gallons out... And ordered a new gear vendor Speedo adaptor. When I swapped from 355 to 323 gears it put Speedo out of wack. Hard to figure milage when odometer is off...