I'm not convinced that orientation of the oil hole matters. With all the pulsation going on inside the compressor crank case it likely does not matter. Even if it did, any sort of front needle bearing / front seal failure would be pretty far down the road.
One way to find out for sure if the hole matters is look at a GM factory manual for a car that uses this compressor ( lots of mid 70's / mid 80's stuff )
Apparently this is the thread
Bad new ac low pressure cuttoff switch?
Correct, oil clocking has nothing to do with a iced evaporator.
This won't cause evap icing.
What is an ETS?
Under charge can lead to icing of the evap because low side pressure is too low causing the evaporating liquid to absorb too much heat.
Over charge will result in high side pressures being too high.
I haven't done a R12 to R132 conversion, but some searching shows 85 - 90 -95 % of R12 capacity.
Try to get some accurate pressures, wait for the low side to get to it's minimum and take the high side at that moment. To calculate pressure ratio, add 15 to each pressure then divide low into high.
From your prior post (low side was like 25 high side around 230-250 maybe)
25+15 = 40 ______ 230 + 15 = 245 _______ 250 + 15 = 265
1 to _______________6.12 _________________ 6.62
According to
https://www.cpsproducts.com/wp-content/uploads/CTK1300A_manual.pdf
R12 needs 5 - 6 to 1
R132 needs 6 - 7 to 1
When you operate the AC, does the discharge line from the evaporator get cold? ( This is the one between the evaporator and compressor ) If the line isn't cold, the system is undercharged.
Too much oil reduces efficiency because oil starts to coat the condenser / evaporator piping. Too little oil won't cause the evap to ice up.
Is your condensation drain clogged?
Do you have a wiring diagram for the clutch control / pressure / temp switches? Something needs to shut the compressor off when evap temp is low or suction pressures is too low.
A factory manual describing how this particular system operates would be valuable.