Digital BW, The Print

Hi,
New to the group - I'm semi retired after a career in high quality printing and prepress with some academic experience too via an MA in Digital Imaging at the London Institute so I have some knowledge of repro. I am posting to find out whether I can do a quick and easy conversion of a cheap Epson CMYK inkjet printer to dedicated B&W. I bought an Epson four colour SX425w a while ago mainly to use the scanner as I also have a six colour Epson for colour photo printing and a Canon as well. So I wondered whether it is possible to convert the Cyan and Magenta carts of the SX425 to Light Black and Light Light Black to get better B&W prints when printing from a B&W original scanned and sent to print as an RGB file. The yellow cart could be another LLB or a clear optimiser. I have prepress experience of doing duotones and tritones by hand with half tone screens and printing them on a printing press so I also wonder if duotones and tritones could be attempted using varied grey inks in the printer whilst using cyan and magenta substitutes on screen. The SX425 was only £50 and as I do not need the printing function it will perhaps be interesting - has anybody tried anything remotely similar.......? Or is it too simple to work?

Pete