When replacing the timing belt on a 2.0 ZETEC engine, the Ford service manual says to use an alignment tool for the cams. It is basically a flat piece of metal, and a screw in type pin. Are these really needed, or is it one of those tools you can do without by eyeballing or measuring? My 02 ZX5 has 82,000 on it and I want to replace the belt before it breaks. On my old 93 Escort GT 1.8 DOHC, all I had to do is align the marks on the cams.