The other thing is I have cleaned the inside as I have gone, not leaving it to the last minute so this last clean shown was only the drop and side bricks. Keep cleaning them bricks whilst the front area is open.I suggest you "blind clean" the inside front, meaning just stick your arm in and scrub, then go inside and do the bits you can see, I ran a small table light into the oven so i could actually see.
All i used was a scourer and water and then a cloth to wipe the muck off. it really only took me 10 minutes to finish it off.