I decided to update my speakers in my 99 s70. There was a lot of information, but nothing comprehensive. This is how I updated mine. I left the dash tweeters and the back deck speakers in place. I decided to just update the 4 door speakers. Although crutchfield says it is impossible, I put JBL 652s (shallow mount speakers) in both doors. You need to disassemble the stock speakers from their mounts. In the front, break off the tabs on the underside & the speaker should be freed. In the back, I punctured the speaker cone with a screwdriver and broke the tabs from the inside. Next you need pliers to pull out the metal prongs that are inside and protrude outside. Mounting the new speakers in the back are easy. Thread the crossover leads through the back of the mount and attach to the speaker in the front. Then seat and screw in the new speaker with the original stock screws. I put dynamat on the doors and then I used Velcro xtreme to mount the crossovers in the bottom of the inside of the door.
The front speakers are oversized and the 652s does not fit perfectly. I drilled holes in the stock mounts then put machine screws and nuts to attach the speaker. Next I used gorilla glue to make sure I have a tight fit. BEWARE gorilla glue expands. Be careful to watch where it may go when it does expand. I mounted the crossovers again using velcro. I mounted them under the bracket and butted up to the speakers. There is one minor modification. You will need to resize the speaker openings on the inside of the front door panels. This does not show from the outside at all. Take the new speakers with the mounts are center them in the original hole. Then take a sharpie and draw around the outside. Then take a strong and sharp razor blade and trim the inside cardboard like material. After this, the fit is perfect.
I snapped off the original speaker connectors and stripped the wires. I then used butt connectors to crimp the leads to the crossovers.
The new speakers sound great. Especially using Dynamat Xtreme speaker kits to help with vibration. With the back door panels off you may notice a rattle from inside the door caused by air displaced by the speakers coming out of the pop rivet holes. After you remount the doors, you cannot hear this.


If anyone needs more info or help just respond.