1994 suburban dash speaker installation

A friend of mine wants me to replace his dash speakers (they are 4x6s) in his 1994 chevy suburban. The only problem is I can't find any instructions on how to get to them... Im sure someone has done one of these before so if you could just post up some directions that would be great.

After best buy got done with installing his new cd player only one speaker works (out of all 6 in the car) so I have to fix that somehow too.

thanks

HELP!!

Alright I installed the front dash speakers today and everything went well...except those stupid clips that hold the grills for the dash speakers on, broke off so now the grill is just sitting there pretty much. I had to resort to some duct tape to hold them down which seems pretty ghetto to me.

The biggest problem is that since he got his new cd player installed (at bestbuy) none of the other speakers play at all except the ones on the dash. I figured that out after I put some new rear door speakers in for him too (infinity reference 6.5s). He has a 94 suburban which has the weird controls for the radio (the tape player is in a seperate pocket from the rest of the radio and there is a seperate tuner/amp below the dash I think also). I'm pretty sure that best buy disconnected this completely when they installed the new cd player but has anyone had experience with this truck? It has 6 speakers instead of the normal four also (two in the dash, one in each rear door, and two in the ceiling in the very back).

thanks for the help so far!