here's a few vids up on YT of some early examples of covers:the HUSK with Kiyoharu, SHADE by Luna Sea, Decoy by DEAD END, Dear Secret Lover by D'ERLANGER. some of these are with the mix band B'ERC~EN~CIEL with members from Ber:Sati, who also played on that show's line-up.

HUSK- http://www.youtube.com/watch?v=VXSfQXuVN...cker=False
if you look closely this is Kiyoharu guesting with L'Arc, even though some people report it the other way. that is definitely tetsu, ken and pero accompanying hyde and kiyo.

SHADE-audio only, not sure which members are playing, definitely hyde is one vocalist as he does frontman duties introducing band and song. ken wasn't with them yet since this was may and hiro left in early june.
http://www.youtube.com/watch?v=3gkVKwpVT...cker=False
edit to add-the TOKIO song was during The Other Side of Heavenly show that was filmed. they did a P'Unk-type maneuver with ken to drums, hyde to guitar, sakura to bass and tetsu to vocals. they put up a spray-painted sign reading KIOTO-a play on names- and performed the Love You Only. that is on video. probably on YT. very funny ending between ken and sakura.
Dear Secret Lover: must be the other band's vocalist, doesn't sound like hyde at all.
http://www.youtube.com/watch?v=uolsggGvK...cker=False

Decoy by DEAD END: this is an audio over various clips of indies L'Arc. if date of 10-27-92 is correct in title, ken is guitarist. they have all claimed to be fans at one time or another i think.
http://www.youtube.com/watch?v=EGVBucwfX...cker=False

if you can, watch all of Sometimes Before 1 & 2, the clips are up on YT. it is interesting as the SB1 has hiro and SB2 has ken. you can really hear a difference in styles as there are some songs played at both shows. and some stuff that later became recorded songs, some that never did.

there are other interesting bits i'll try to locate. but not today. i have exhausted my bit of laruku posting efforts for the day. >.<

i haven't found the link to the discography article, but here is the L'Arc~en Cyclopedia where the video post-person got some info. the site has one of the good lyrics sources, although i disagree on a few bits of the indies songs. they are based on listening, not written lyrics translated, so anyone's guess is as good as another. ^ ^ http://haruka.baka-koneko.com/

hope i didn't screw anything up. not gonna spellcheck, may be a mistake. have fun.