hey man don't get overwhelmed. It's relatively simple and not too expensive even if you went the installer route. I took out my six disc because i couldn't get the input to easily integrate into a relatively inexpensive receiver (like the rear usb or aux). Not a big deal for me because i use my phone for bt pandora and have xm radio (addable once you get aftermarket receiver). Anyways. That tape deck space will not accomodate a cd receiver but instead a shallow (less than 4") digital media receiver. I researched the ish out of all of the currently available options and found that JVC was the best at the time but I'd rather have pioneer (all the pioneers were 2v at the time). Low and behold, this units is now available for $20 more than what i paid for my JVC and is 3 sets of 4V preouts.
MVH-S501BS - NEW! Digital Media Receiver with Enhanced Audio Functions, Improved Pioneer ARC App Compatibility, MIXTRAX®, Built-in Bluetooth®, and SiriusXM-Ready™
here's the jvc if $20 is a breaker
JVC KD-X340BTS
As a reply indicated. Find a matching resister, tape it in, done. The aftermarket radio will be wireed straight to your ignition and antenna so it will operate on and off as the car...so just like factory
as for all your speakers, deal all that old factory s*** and get something you can really crank up. Simple component set up front, solid coaxial set in the rear doors and you'll be good unless you want to add bass. Then you get a simple stealth box with an aftermarket subwoofer amp later. G
Going back to the part about the six disc. I mounted a four channel amp that was pretty much the same size as the six disc. Even used the brackets that held the six disc upright. only reason my cupholders had issues was that my rca's were 16' and only needed to be like 4 feet max. You could add a small four channel amp for your components or run them off the aftermarket receiver.
anyways, sorry for going crazy on stereo recommendations. Im a stereo fanatic first