I beleive the 93 TPS needs to be adjust for proper voltage after being installed.
I had the same problem on another car, its not 'plug and play' like the newer ones are.
I can't help you with the cluster issue, sorry. Hopefull someone more knowledge will chime in shortly.
The heat/ac not blowing strong could be a clogged up core.
Heres a procedure to clean it about 1/3 od the way down the page, though it might be up in TechInfo also.
Not blowing very warm or cold could be the airmix actuator. Search oin that term and you will get alot. I beleive your year can pull codes thru the Ecc if you have it. Also your ecc needs to be calibrated, if I remember correctly. Hopefully its as somple as that.
The o2 sensor is on the rear (firewall side) exhaust mainfold. Its not to hard to reach from the top and It could be leaking if its loose.
98 SSEi 111,222 miles.
Intense PCM, LS6 Valve springs, PEMS, FWI. Hawk Street Pads.