What is the best weight oil and brand to use in my 1994 T-Bird with 107,000 mi?

Oddly enough my information did not provide weight of oil recommended by Ford in their information. All three engines that year use hydraulic lifters so a lower viscosity oil is recommended over a straight weight oil. !0/30 would be good,most oils are good particularly if changed every 3,000 miles. We use Chevron oil and tell customers change oil every 3,000 miles. Many of our customers have 200k to 460,000 miles on their cars.