lkdearing

As it is a single rail are you fitting a J type overdrive? If so, Canley do a rear mounting plate for just this occasion. I found the D type plate to be a little low.

The Spitfire Mk4 (and 1500 and GT6 Mk3) are supposed to have 12" blades. These are nominal sizes though as my Spitfire blades are 11.5"....! The arms are also approx 11.5". As to them meeting in the centre, mine never have either.

You need to remove the upper and lower stop brackets (red and orange), remember which goes where! Then wind down the window until the winder disconnects from the lower channel. You can do this now the stop brackets are removed. Then unbolt and remove the rear channel (green). You should now remove the outer rubber strip and inner seal along the door top. The clips will fall into the door for retrieval later. This will now mean you have the space to remove the glass and lower glass bracket. To remove the glass from the bracket, heat up the metal to soften the rubber insert and carefully prise away. Note dimension for refitting. i used Tiger bond as the rubber seals are impossible to refit without risk of breaking the new drop glass! Best to renew the seals in the glass channels front and rear at this point. Refitting is a reversal of the above. Slacken off the regulator and runner bolts when fitted to adjust for fit and remember to refit the upper and lower stop brackets. Take your time and you will make a good job of it.