The useful number is the combined haul, not one component at a time. Add every stack and check whether the safer recycler is worth the lower return.
Count full stacks and leftovers
Small leftover quantities can round down, so enter the actual amount instead of estimating from full stacks.
Choose the recycler first
Safe-zone and monument runs trade security, travel, and output differently.
Plan the return trip
A large scrap and high quality metal haul deserves a clear route home and enough inventory space.