Noob with a K20 Burb

[Mojave K20]

Hey! I have a K20 Suburban with a fresh Goodwrench 350 to play with. Had this truck since 94, daily driver which means long trips to town for groceries, 320 miles round trip or so. Has a 4 speed standard. My mileage with the old engine and the 4.10's was about 15 on a good day. This last trip, looks like 13 or so. But there is only 550 miles on the new 350 so we will see after the next trip. Maybe someday I should get the AC fixed since summer temps here are over 115 if not 120 all the time.