Oh! I'm sorry! I misunderstood you! Gocha now! Well...
Whenever I'm looking for a spread for a legendary or whatever, I usually use a program called PokeRNG. Most people use it for finding shiny spreads reeeeeeeeally fast, but it also works for non shiny spreads, and is much faster than the RNG reporter too. I just put the "max delay" setting on like 30,000 and it gives me stuff up to like 3000ish. 99.999% of the time, there are better seeds with MUCH lower frames on higher delays.