Given that the area above the drop ceiling is really the cold-air return plenum for many office building HVAC systems, there's some pretty nasty stuff up there.

I've done enough time crawling through ceilings running CAT5 to know that's not a job I'd want to do again.

Best to outsource it to a local telecom company or the building maintenance dept (especially if they're in a union and "own" the job).