Not to get into a details thing here, but it does not usually matter with this class of machine which drive has the terminator as long as one of them does. At least my experimentation shows me this to be the case.
I would start by swapping the jumper settings. Make sure you write down what they were for each drive and then reverse them. Try that. Jumpers are switches. Some drives have a little set of 5-7 on/off switches, some drives have little clips that fit over exposed pins. You'll see them with labels "DS0/DS1, etc. If changing jumpers does not work or the jumpers for each drive are the same, then you will have to swap the drives physically so that they're at different points in the drive cable.
And if that does not work, swap the terminator. It will be a usually colored differently than the rest of the chips.
My concern is that you only remove drives and chips if you have to, jumpers are not easy to break, and you can always put things back the way they were.