I might be mistaken but to my understanding, the EPSON B-series cartridges use an ink bag design, no drilling won't work. They are similar to the EPSON wide format cartridges. If you want to refill your originals, you need to inject ink through the exit port just like the Epson wide format...
The Series 21,22,23,24 cartridges cannot be refilled due to the chip. This is just like Lexmark's Return Program.
However, the 21R, 22R, 23R, and 24R can be refilled but the ink level will always say low (like Lexmark 100XLA).
That's really scary news.
Any luck on overriding that feature to let you use the color inks even if empty?
As for advice for overriding the ink level monitor, I own an 8500 which is the predecessor with refillable cartridges using the original chips. All I can say, is just ignore the messages...