There is no need for any mod chips! Go to any mod-chip site (i.e. www.mod-chip.com) and look for the slide card, with it you can play both burned dvd-r & cd-r games by swapping the SWAP MAGIC discs that it comes with. And you dont need to install anything or open your ps2 all you need to do is carefully remove the front cover of the ps2 tray.
OR
Go to Yahoo and search for Top Secret Mega CD or go to www.howtocopydvds.com ,when you find the site selling the product, order it and with it you can burn dvds ps2 games (both cdr and dvdr) WITHOUT a dvd burner! Along with xbox games. The neat part is...when your burning xbox games you can format it so that it can play on ps2 consoles and ps2 games can play on xbox consoles WITHOUT the need of any modchips to play the burned games!!!! The game system reads the disc as an ORIGINAL!!!!