Unable to change firmware from Gargoyle 1.6.0

[Adventure2000]

I have installed Gargoyle 1.6.0 on a Linksys WRT-54GL and it is very slow. I have now noticed I should not have installed this version but it is too late. I have tried downgrading to a lower version, tried to switch to DD-Wrt, Tomato and the Stock firmware, none of which seem to take. I have tried through the web interface and via tftp on windows and mac with no luck. Through the web it says uploading update and the router reboots automatically but no change in the firmware. Unable to get a successful connection through tftp although I have been able to in the past using tftp2.exe before I flashed it to this Gargoyle version. I tried several times rebooting the router and trying to catch it in its boot cycle to update. I do get a ping response from it during boot but it is generally after 20 to 30 seconds after power up before I get a response. Any ideas would be helpful other than the jtag option.

Thanks in advance!

[DoesItMatter]

You will have to do the DD-WRT TFTP recovery method

Use one of the DD-WRT images to flash back when you do this

BUT

You need to do this on a Windows XP machine or if you have
some Linux knowledge, you can try a linux machine recovery

Windows Vista / Windows 7 / Windows 8 have upgraded the TCP/IP stack

You have to put a dumb-switch (pure switch - not router) between
the computer and the router if you have any of the 3 Windows above