Disconnect the vacuum supply line connector, which is right beneath the AC lines in the engine room.
"CAUTION: discharge AC refrigerant before disconnecting AC lines! This needs
special tools or professional support."
Remove two AC line connector covers.
Disconnect AC lines. Insert 5/8 disconnecting tool to small and 3/4 one to large line, respectively. I used "Lisle 37000 Air Conditioning/Fuel Line Disconnect Tool Set".
While inserting the disconnecting tool, pull the line on the right side until you see gasket (green in this pic). This step gets easier after removing two heater/AC unit mounting bolts securing AC accumulator (beneath the two A/C lines in the pic), by which the large line becomes more flexible. If you want to dismount AC accumulator, skip this and do the following several steps first....
After relocating the spring clamp (arrow) using a channel-lock pliers, disconnect the upper heater hose. I coated the connection part with hot soap water and twisted the hose left and right using channel-lock pliers. Covered the hose with towel to prevent from damage.
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