94 E420 Air Pump Removal - What would be the size of the new belt?

[pesuazo]

As the title explains, I want to remove the air pump.
It is noisy as hell (bearings). I do not want to replace the bearings, just remove the whole thing and put a new belt, which evidently will be shorter.
I found a few threads, but only for M103 and M104 engines.
Have anyone done this on a M119 engine?
What would be the size of the belt with no air pump?

Thanks,

Pesuazo