I was going through the same issues and did a LOT of research and came up with this.
Atoto S8 Gen 2
Full touch screen Android so you download all the apps you would want. Fits Perfectly to take up the 2.5 din spot in the'86. the screen would just sit outside the bezel on an '87-'89 a little more
With a PAC SWI RC1 (has to be this exact model - other brands/models will not work) you can assign the steering wheel controls to anything you want (I have one button programmed to switch to back up camera so I can see how fast the cops are gaining on me - kidding)
It has GPS, TPMS capabilities (just need to buy the wheel sensors), back up camera (no camera included), 2 bluetooth channels so I have one for my phone and the other for a bluetooth adapter attached to my Megasquirt so the screen acts as a digital dash for anything I want to monitor on the engine. SD,USB (installed an SD extension and mounted it in the storage bin below the radio and installed a usb extension and put a 2 port receptacle in the center console). SO many adjustments for the music, bass boosts and you choose the frequencies, multi band e.q.'s 1 for the front speakers, 1 for the rear speakers, time delays for the speakers, where in the vehicle you want the sound field (balance/fader
Customize the color/layout to whatever you choose.
You can use it as a dashcam DVR with an added front camera.
I did have to mount mine with the chassis adjusted all the way up and at a steep angle to clear the hvac ducts
Blue tape to keep protective film on it while finishing the wiring.
