over 600 feet 10 feet of drop...2% slope is 2 foot drop every 100 feet, if you use a ladder at the highest portion of your bush and tap high you might be able to get it. My sugar bush is very flat as well some of my mainline is closer to 1% but I use a traditional vacuum pump I am under 500 taps.
Like LMP Maple says 1" all the way, it's way more forgiving, keep your mainline tight, use #9 wire (wish i had done that, all my new will be #9 instead of #12). A retired diary vacuum pump would allow you to get a sap ladder half way and give you two slopes that are better, a diaphragm pump i have no experience with.
2024 - 57 Gallons - Short season, many and varied problems remedied in short order! - No buckets!
2023 - 38 Gallons - RO broke, Buckets didn't run, rebuilt vacuum pump mid-season, still made good syrup!
2022 - 52 Gallons - DIY RO, 50% less fuel, no late nights in the shack!
2021 - 48 Gallons - new pans, new arch, lots of new taps and tubing
2020 - 32 Gallons
2019 - 27 Gallons