i think 5oz is the whole system??
after some further searching
"When you replace the condenser you need to add oil to it. The correct amount to add to your condenser is **40mLs**
i would think you would add oil to the hi side condenser port (bottom port) so that the oil is forced through the unit vs just sucked out the other side??
there's a PDF on 1st post of the DIY, it has oil needed for condenser.
and to note, step #6-7 on the DIY for filling 134a is not proper practice. on an empty system you fill by weight as prescribed by the AC sticker on vehicle hood, my 2006 GX470 says 1.69lbs (27oz) max. 1.5lbs (24oz, two 12oz cans) is about middle of the allowable range per the sticker i have.