How many O2 sensors does this truck have and where are they located?

Jacobandnickolas, they are but the one at the y is plugged and there's no connector for an O2 there. I've been told the 94 only has one on the left side. My problem is still high HC at idle. I've replaced about everything and it keeps getting worse. I've replaced TPS, ICS, EGR solenoid, air filter, distributor, cap, rotor, wires, spark plugs, coil, set timing to 0 with spark wire unplugged. Rebuilt TBI and had injectors serviced replaced vacuum lines can't find any leaks replaced O2 non-heated sensor. (May have done a couple of others but can't recall right now) just remembered did PVC and replaced gas cap. I've done three tests at idle they started at 302 replaced things then went to 404 replaced to where I am now and today, they measured 532 the max is 220 the high RPMs went up then down but are way under the 220 limit at 102. Not showing any error codes, I've been working on vehicles for a long time and have run out of things to try. Just rebuilt lower end new rings etcetera replaced thermostat when put back together. The truck is running fine no misfires, starts right up no missed through gears, could spin out if I could afford the tires, vacuum reads 17. The mechanic at the emissions said the truck was running great. Any help or suggestions would be greatly appreciated. Mike D.

Sorry, missed that Joe gave the answer. Appreciate the answer.

I started this as an O2 sensor question that was answered by Joe. I thought I'd put this out there again to see if anyone has any suggestions.
JacobandNickolas; My problem is still high HC at idle RPM's (710). Passes the Catalyst, Excessive Smoke, PVC, Fuel Evaporative Controls, EGR, Fuel Inlet Restrictor, Gas Cap test Result, and high RPM's (2563) I've replaced about everything, and it keeps getting worse. I've replaced TPS, ICS, EGR solenoid, air filter, distributor, cap, rotor, wires, spark plugs, coil, set timing to 0 with spark wire unplugged. Rebuilt TBI and had injectors serviced replaced vacuum lines can't find any leaks replaced O2 non-heated sensor. (May have done a couple of others but can't recall right now) just remembered did PVC and replaced gas cap, vacuum reads at 17 inHg vac. I've done 3 tests at idle they started at 302 replaced things then went to 404 replaced to where I am now and today, they measured 532 the max is 220 the high rpms went up then down but are way under the 220 limits at 102. Not showing any error codes, I've been working on vehicles for a long time and have run out of things to try. Just rebuilt lower end new rings, bearings, etcetera replaced thermostat when put back together. The truck is running fine, no misfires, starts right up, no misses through gears while driving, could spin out if I could afford the tires. The mechanic at the emissions said the truck was running great. Any help or suggestions would be greatly appreciated. Mike D.

All the suggestions were addressed in the original question. If they'd read the entire message, I was asking for some ideas on what to do or check next. The response didn't add anything to an already frustrating problem, but thanks anyway for your help, I just wish it were a little more helpful.
Mike D.