Another stupid digital to analog swap question,

So I have a 1987 N/A GLL,started with the digital but after I broke the tach I figured it was time for an analog swap, hoping to keep this car a long time and I don't wanna have issues down the road. This started a terrible cycle of trying different harnesses and clusters. So the first cluster and harness I tried was the analog out of my 85 N/A with it's harness, all sorts of weird stuff happened including the headlights having a seizure,the dash illumination clicks on then the the clearance illumination fuse blows and it stops working, lights get stuck in whatever position they were in. After swapping back I searched for solutions and decided to pick up a 1987 analog for the best chance of compatibility, it also does weird (but totally different) things. First thing it does is when the key is on the right turn signal indicator on the cluster stay on, when headlights are turned on the left turn signal and brights indicators stay on. Lights stay up as long as the cars on and turn signals function and relay clicks. Still no illumination. So in order to still be able to drive it (I have to daily it, it's literally my only way to get to work.) I tried on a whim using the 85 dash with the 87 harness and I get tach and no weirdness, no illumination still but fuel gauge works and so does the temperature, turn signal indicators work as expected. No speedometer but I think the cable I swapped in was broken. I have swapped out the fuel sender unit and bypassed the stop/headlight sensor as suggested by many online guides. There are three of us working on the car and BEFORE it's suggested I have all the FSMs and we have poured over their terribly vague diagrams for hours just to find no answer to why this still isn't working. Everyone who has a write-up or guide is either for the earlier models or the guide has disappeared from the internet. almost all results I've found are someone asking a question like mine and 3 people hastily replying "Get the FSM" without any further helpful information. I signed up for this forum in hopes of finding anyone who might have any leads on something that might have blown when I put in the 85 harness and cluster or maybe something I haven't swapped in that could explain this weirdness. all fusible links are tested and good. At this point I either need an expert or a priest. If anyone has done this on a 87-89 before and had success I would really appreciate just a confirmation that it can be done.