Oven cleaning is not easy work, even if you have the right chemicals and machinary.
You will need an electrical soak tray. Which heats the chmical to a certain degee. you then place all of the oven racks and plates, grills into there while you are cleaning the oven - hob.
Becareful on aluminium most oven cleaning chemicals will blemish aluminium, some will even mark stainless steel.
you will also need to know what to do on self cleaning ovens... you cant always use chemicals as it damages the surfaces on these.
I wish you best of luck, but dont think its easy.. its not and wear extra long gloves that cover your arms, trust me its messy even on the cleanist ovens...
Get your self a good light, to shine inside the oven... to look for dirt, grease, chard food.
After a while you may think its not worth it.
Dapper