Product Options for Pizza Shop

hi,
Using opencart_v1.5.1.1 for pizza ordering. Made most of the changes to the default code to suit the pizza shop.

http://forum.opencart.com/viewtopic.php?f=20&t=46318
http://forum.opencart.com/viewtopic.php?f=20&t=52446

but now i am struck as the client wants me to have
1) pizza topping selected as whole or left side or right side
2) Set the product options for topping selection.
eg: 1 LARGE PIZZA, 3 TOPPINGS costs $10.00 (this includes 3 toppings which a customer can select).
but when a customer wants to add additional toppings, the price of that selected toppings shall be added to the pizza price.

Attaching screenshot of what i need(Topping selection).

anyone having done the above customization?

Thanks...