i have a 6m with 272 regrind cams begining to to go flat and i bought a pair of stock 85 5m cams still in the cam towers from moonpie33. my plan was to have them reground to 272 as well but talking to moonpie, he said he thought it would be a better idea (cheaper) to have the cam towers shaved so that the cams sat closer to the valves, thus making more duration. anyone else try this? or have any advice? also, how much would need to be shaved from a set of stock 1985 5m cam towers to create the equivalent, or maybe even a little more, than a 272 duration. thanks for the help!