I had a single nozzle pointing into the supercharger outlet on my M45 coldside kit, and I don't believe that I had even distribution.
Based on staining from the dye in the blue windshield washer fluid, most of the water went into #1 and #2 cylinders, and there was no evidence of any water going into #4.
I would not recommend a single nozzle, post blower, in a coldside.
Perhaps two nozzles, one centered between #1 and #2, and a 2nd biased slightly toward #4 might be safe, but if I were to do it again, I'd go with individual port water injection.
Here's my manifold "cover plate" which goes on the bottom of the M45 coldside, not on the top, like the M62. The water injection hole is the single hole near the top:
You can get sense of how it looks installed here:
