Spot color is really hard to get good results from. Have a go at a de-saturated look. So not quite B&W, but tone down the colors a bit. Not sure if it will work, but worth a try.
Got some new wheels the other day. Was an absolute bargain. So cheap to get around on, just cant carry a whole lot, lol. Also slows right down going up big hills, but you get that. Better than not being able to go out at all cause it costs too much to fill up the elgrand, lol.