Got a '99 with almost 1k miles on a Vortech. She burns a tiny bit/(or loses it, some seeps out of the front cover), but I just check it frequently. Got a spot on tune, and just make sure there is always plenty of gas in the tank. If she gets spot on gas mileage 16-19 city and good hwy mpgs, she will be good to go, weak compression will kill gas mileage, if she is well maintained you will be fine!
Go with the svt focus pump you got, should be good for around 450rwhp. Go with 42# injectors, those'll do you til 500ish! A intercooled procharger setup will net you between 380-440rwhp IMO, depending on the boost you run and tune you get! Maybe invest in a boost a pump if pushing closer to 450rwhp.