Two years ago I stripped a rust hulk - 7F01C1291xx - 289, AC, tilt, convenience control, and more. This thing was parked in 1979 and super original. Original FoMoCo belts, striped vacuum lines, etc. Only the oblong can. No evidence of two in terms of hoses, tees, clamps. There was the unique plastic tee under the dash for shared vacuum between AC and tilt. I did pull what was the remains of the rusted battery tray - pictures included here. No holes to support a vacuum canister in terms of the pictures. I did save the tray and can pull it out to make sure.
This could simply be the way Dearborn was doing it this week...