82' olds 98 obd1 code 21 help

I have an 82' olds 98 coming home today check engine light come on. so i get home probe the A and B terminal and i come up with code # 21. i looked up the code says Throttle Position Sensor High Voltage. It has the 4 barrel carb so im not sure where to look exactly. And when i find where to look how do i test what is the problem? Thanks

The tps is in the carb, make sure the connector is ok, then replace it, for a picture of it try autozone.com, repair guides.