1991 Mighty max Down

Hey all, got some problems here.

I'll start by addressing the main problem; She won't run. I'll turn the key, she'll run for a minute (horribly) and after I gas it a few times with minimal response she starts to die down and stall out. same effect happens with the brake pedal, I noticed it was awfully stiff and got stiffer, vacuum issues? Before this final crapout I had zero low end, it would take ages to get to speed coming from a stop and bogged on every hill I encountered.

But for how we got here, I might have a good idea. I changed my sparkplugs & wires (spark plugs were actually surprisingly healthy, but a little dark if anything after 10k) and while doing that I changed my ignition timing, realizing I goofed without grounding the wire I went back, did it again and it was fine. for a while. then some hot days came and it hasn't been the same since, on very hot days I get horrible vapor lock and have to take my cap off to release pressure (fuel filter has been replaced, have a pump though). but even still it was just sluggish, and just wanted more timing to run correctly. at some point in there I messed with the throttle/tv cables to try to get more out of it, as well as the idle air mixture screw to not stall out at lights. a few days ago I ran out of advanced to give it and now we're here. When it would idle I pulled the wires and checked spark. it was hitting on all of them but a little weak and spotty on #2.Wondering if the ECU has finally crapped out (did smell fish on some hot summer days) or a component in the distributor. please help!! this is my only ride, and I love this truck, and I don't want to get rid of it.