<VV> Couple of A/C questions - limited Corvair

[Grant Young]

I am in the midst of replacing the air conditioning components on the wife's 2005 PT Cruiser. The compressor was blown and low pressure line had a leak (after only 38k). After two days of removing parts to get to the compressor and dryer, I turned them up to drain the oil so as to replace the same amount and neither part (or either line) had any oil in it. My question is whether it is possible for it to have been blown out when the compressor went or if the leak in the hose let it all out which led to the compressor failure (I guess the low pressure switch didn't work?). The manual is unclear as the amount that should be replaced as it says to put in an ounce when you change the compressor and in another section to put in an ounce when you change the dryer, and I am wondering if I need two ounces or one. The spec table says to check the data tag on the compressor but it doesn't have that info.

Question two is about the type of oil to use. Seems there are 4 different viscosities from light to heavy and all the compressor tag says is HD-8. Does anyone know what that means? (I plan to visit the dealership tomorrow as I can't get any help over the phone). 

As an aside, if you own one of these or are thinking about buying one, be sure to purchase an extended warranty that covers electrical and air conditioning. It comes with a 70K one that only covers the drive train. I had to remove the grill, radiator support, weather stripping, electric fan assembly, air cleaner, battery and tray, cruise control, power steering reservoir (with resulting loss of fluid) etc. just to get access. I should remove the radiator for better access, but it's just too much trouble with all the connections for the cooling of the turbocharger. You will also have to buy a complete brand new liquid line as the orifice tube is somewhere inside. While removing the dryer, I noticed that the alternator is also completely inaccessible down behind the engine next to the firewall and that a simple thermostat change is out of the question in the home shop. 

Thanks for any insight on the oil.
Grant