You will need to swap all the trucks computer wiring and easiesr will be stand alone harness . Or a 411 comp with 97 wiring.
TRansmissions may be same length but apples and oranges Need to know exactly what trans .
JUst did a 92 1500 cab on 94 k2500 frame had swap all interor wiring and under...
Looks good , with what i know now about these frames i would add a bolt on skid plate from bottom of the bumper to the crossmember for the lower control arms using 2 braces in a H pattern with skid plate under it . The frame horns just arent like early 80's trucks.
Rebuild engine cam swap .430/.450 int/exh if keeping tbi stock. Add 2-3 degrees timing just before check engine light comes on driving.
182k not worth sinking $ just to break something.
If it was mine 5.3 ls swap
I Prefer edelbrock carbs on daily drivers with steady vacuum , no choppy idle engines.
High perf holley but you need to know how to tune. 90% of problems i see are powervalve related.
I check power at the fuses with a test light with meter to see voltage from ignition switch . Have seen 6 ignition switches bad in 7 months and i dont work much maybe 1 truck a day
I Have also seen the fuel pump power wires corroded in frame rails from a professional moechanic probing the wires...
Scan for codes check fuel pressure . Cat could be starting to go . Just had a knocking 2002 trailblazer got it for $500 bad cat insides were pounding. Flipped eady money.
UPstream o2 sets your fuel trim iirc downstream is cat performance.
NOrmally i would replace the 2 upstreams and retest. Even amazon carries o2 sensors.
I Just did a 94 to 92 cab swap had to change the dash wiring computers all of it . Cluster everything was different even cut firewall for the larger plug for computer harness. Took a day to rewire . Worked great until owners nephew plowing snow wasnt stopping in reverse broke everything so bad...