When i bought my 59 3000 Mk1 it did not have a tacho drive housing fitted and the disty had been replaced with a later type fitted direct to the block. I now have sourced a tacho drive and a correct disty and am trying to fit it. With everything in place and the drive meshed correctly to the cam and the slots all engaged as they should be the tacho drive housing sits about 3/8" or so off the block. It seems physically too long to sit down correctly with the flange of the tacho drive against the face of the block. Any suggestions as to what is going on here would be greatly appreciated once again.... Thanks Richard