For the purpose of 1st April Fools Day I have originaly titled this solution a "CPU controlled MLU". Actually, this workaround was used as a necessity when the ancient Nikkor 8mm f/8 Fisheye came my way. I just wanted to try it on D70, but it's long protruding back element was coliding with D70's mirror. Squizing that 20-pin chip (of course, it can be anything being 1 inch long) underneath closed mirror provided for mounting 8mm lens.