This is my 3rd iteration of this design.
A sushi belt all in one Kovarex Uranium fuel Refinary.
A single belt feeds 32 Centrifuges, these then output U-238 onto a Sushi belt. The Sushi belt will only allow more on if room becomes available, this then feeds into a looped set of Kovarex refinaries, only one side of the belt is fed allowing for the Kovarex refinaries to dump excess U-238 onto the belt.
In the middle a set of containers will collect Excess U-238 and only feed back onto it if there is room, this will hold 24,000 units. These units then send a signal to the input belt to stop if the total stored contents go above 1000, this will help if you only have a small field of Uranium Ore.
The Kovarex refinaries then loop refined U-235 into a container, once the container exceeds 1000 units of U-235 it will then feed the Uranium fuel factory.
In the middle of array a Spent uranium facility is installed which will dump into the array.