I wouldn't do the PS swap to manual IF, the car it is coming from is over 200K due to wear, if there will be a lot of around town driving or lastly if any drivers of the car aren't strong enough for manual steering.

Had a 115 manual steer when I was young and wouldn't want it today.

Taller sidewalls will make the car less stable, wider tires may make steering harder.

Good luck, if you do the swap please post the results.

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