How do I unbrick a Linksys WRT54G v.5 router?

Hi, I was upgrading my Linksys WRT54G v.5 wireless router, and in the process of it my power went off. Now as I want to access my router page "192.168.1.1" I am unable to. The page would take awhile to load and then it would display an error page. Also the rectangular orange light that used to glow underneath the "Cisco Systems" on. I have tried holding down the reset on for 30 seconds and unplug it and plugging it back in while holding down the reset on for another 5 seconds. However I am still unable access my router page, I have also used "Draytek Router Tools" and all I have been getting with that was router was not responding. Power still flows in and out but the firmware is completely screwed. Now I don't know how to reinstall the Linksys firmware back into the router. Finally I tried chatting with an Linksys online support and she can't offer me any help because my routers out of warranty. Therefore I am asking if anyone knows how to unbrick a router without actually opening the router apart itself. Thank you very much for helping.