What is maximum level to refill 3800/3880/P800 cartridges?

When I initially filled the 3800/3880/P800 IJM cartridges, I followed the directions to fill each with 60 + 10 = 70 ml of ink. Today, I was refilling the carts and had just a little left in the bottles, but didn’t know how much I could add to safely “top it off”. How much vertical distance should the ink level be from the fill hole? Thanks

leave 1/4 inch of room at top about

best
Walker

Thanks for the info, Walker!