No problem Paul. Just a few pointers that should make things easier.
Get all the racks out and put them in the grill pan or if there's a roasting tray in that. Spray them and leave them until the foam goes and the carbon is dripping then get them in the sink and give them a good scrub with the brillos.
Same with the oven, spray it and leave it, but be careful if there's a fan at the back, don't spray directly into it. Wet rags to clean it out as the brillos might damage the coating, so go easy if you have to use them.
Arthur