The TPS should be a direct swap, not requiring any changes for the 0-5V reading. The Idle Air Control (IAC) valve is in charge of how much air gets thru during idle.
If you're experiencing something odd, I'd focus on hunting fir any vacuum leaks (a hose as a stethoscope works great). It doesn't take much for idle to be affected, and the IAC may not have enough impact if it's a big enough air path. You can also swap IAC valves to ensure it's not that component causing an issue.
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