"1020" grams is not close to "100" grams. Did you mean to state "102.0"??

Is this an R134a system or R12 system?

Most folks I know put a set of gauges on the high and low AC fittings and fill to a pressure, but I guess the quantity process would work.

__________________
There is a very fine line between "hobby" and "mental illness."
FrankenBenz: '87 560SEC with an '02 cammed LS6 and custom 4L60E.
Bling: '87 560SEC, ported/polished, lowered
Lisa: '87 560SEL, lowered