Motor running hot

[1968CHEVYC10]

Finally got my her to start few days ago. Anyway today I took it for a test drive probably about ten minutes or so, and when I got back the was a good amount of smoke coming from the engine around the exhaust manifold, and it seemed to be pretty hot. There was a small leak around the lower coolant hose but the the coolant was only about 2 inches below the cap and it wasn't bubbling over. I just changed the oil and coolant today, so it had plenty of oil and wasn't leaking. One thing I noticed and thought might be an issue was that the oil cooler lines were not there and the holes capped off. Did these motors even have that? the motor is a 350 probably an early 70's.
Thanks for the help yall.