Overload test (165 PSI net) uses the same flow and setup as the capacity test. Your apparatus's rated capacity is highlighted. Multiple tips = identical tips flowing simultaneously; pitot each tip and sum the flows.
Setups keep pitot readings in the 30–90 PSI band for accuracy. Each line = two 50-ft sections (100 ft), ~350 GPM max per 2-1/2" line, siamesed into the appliance holding the tip.
Lays are suggestions — NFPA 1911 does not mandate one; any lay delivering the target flow with a solid stream is valid. Multiple tips: pitot each tip, sum the flows.