I have a 300 Hurst with 77,044 miles on it. Drove it about 10 miles then changed the oil. I used 10W30 Valvoline oil and Ford Motorcraft FL-1A oil filter, the equivalent of Fram PH8A oil filter. Oil filter removed was FRAM PH8A. After changing the oil, the oil pressure light stayed on ( no oil pressure gauge on my car ). I replaced the oil pressure sending unit to the oil pressure light, but still the light stays on, so apparently no oil pressure? Any suggestions on resolving this oil pressure problem? I considered removing oil pressure sending unit and installing mechanical oil pressure gauge to confirm no oil pressure. Also I talked to NAPA about a new oil pump - they sell a standard one, a high performance one, and a high performance and high volume. Which one to buy if it turns out to be a failed oil pressure pump? Thank you. Steve in Columbus, Ohio.