I really have no idea. I would just go by the numbers in the guide - they are pretty consistent with what I have seen here.

If you're filling with R12, you can use the sight glass as an effective method of gauging your charge. Just fill up until it's almost clear, with just a few bubbles floating past. You want to avoid a "foamy" appearance in the glass.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280