As with most older cars, my 1994 e36 shows definite deterioration of the rubber hoses. I'm looking to replace as many as possible ASAP. The first set that I'm focusing on are the heater hoses (?) which extend out from the heater box back near the driver's side left of the engine; these seem particularly hard to reach. Can anyone advise me on what size these hoses happen to be? I'm looking to avoid a coolant leak and judging by the appearance of these, I may not have all that much time to find replacement. The Bentley manual also recommends emptying the freon and engine coolant from the system before attempting this job. Is this necessary for hose replacement? Just checking. Thanks!