Everyday stock 5.3 swap into 87 r10 swb

[Fishjeepchevy]

After a while battling some wiring and common little things it fired right up used a surge tank from a late model truck and filled the system from there. scanned it and it had a knock sensor bank 2 circuit low signal. What would be the deal on that it also threw both o2 sensor heater codes and both o2 sensor inactive codes. When i started it an ran it for a while it had kind of a high idle with minor fluctuation but I cleared it out and it idled down to 600-700rpm