You have it sussed! there is no magic involved.Spray/wipe some diluted washing up liquid around the glass where it meets the rubber seal so it slides easy,on the LONG edge in the centre use a wide wood chisel/strong paint scraper at about 45deg and tap it upwards(you have to be very firm and confident, I can tell you are) the plastic beading will bend and pop up in the middle and you can lever it pull it upwards by hand,do the next long edge (the top prob) then the sides.The glass will sit on plastic spacers to lift it up off the frame and there will be a huge amount of clearance between glass and frame,measure the glass in situ you may well pick up the correct size at a large UK diy store off the shelf.Put the new glass in soap it up and fit beading in reverse,short lengths then long,put a piece of wood (2x1) flat against the glass and tap down on the beading(firmly)and it will POP in.It is as easy as you think it will be.Commom sense and confidence.Good luck.
Rich t, April 2014
