What Mod do I need to carry out - MK1 Hood/frame fitting a glass window With Mohair

 Hi all,
 I have just bought a heated rear glass window for a 93 MK1 Eunos.  I plan to go to Jack Smiths in Swansea to get a new Mohair hood fitted.
 I just want to find out what is the mod required to the frame of a MK1 to enable it work with a glass window fitted.
 Do I need to buy a Mod Kit or is it straight forward to Mod the frame myself ?
Cheers
Trikster