I get tempted at times to start modding things. I've changed the steering wheel and had to replace the exhaust. I bought the car with oversize rims, but I what to go back to stock.
Investing in (no wait, it's not an investment...it's spending money) modified parts will change the car. The only mods I do are the onces that I can reverse. I keep my stock parts in storage, just in case.
I get a kick out of other RX7 guys who look at my car and say, "Is that a stock radio? Is that the stock intake? Where did you get the battery cover?" It's original!!