If there was a restriction, you should be able to find it easily. Normally it will produce an ice ball, and you will have super high high side, and or super low low side.

My experience with mb Ac systems is that you should just charge it by weight and don't look at the gauges. My vague recollection of my 300e was that the pressures were high after about half the r12 was in. I just stuck to the scale and I had perfect Ac after.

__________________
Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2