I came across a 302 so im rebuilding it and eventually will put it in a car. Its a 1979. It didn't have a dipstick tube when i got it. Where does the dipstick tube go?
that will depend on what it came out of. truck motor had it in the oil pan ,drivers side .that pan will not work in a mustang with stock suspension and will have to be replaced with an early pan. the timing cover would have to be replaced with an earlier cover that has provisions for a dip stick.
if it is from a car it should still be in the timing cover,passenger side right behind the ballancer .there will be a 3/16 hole that passes through the timing cover into the front of the oil pan. the dipstick and tube just pushes in and the tube bolts to the head at the top of the tube.
It's possible you got a truck motor, as mentioned and someone put a car pan on it to make it fit, without pulling/changing the timing cover.
What are you planning on doing with the motor? Easiest thing to do would be buy the pan, timing cover, & timing set for the car it's going in, and using the dipstick tube specified for the car.
One of my timing covers I got in a trade was a cross over year one. It had the hole for the dipstick tube on the passenger side in front, but had a tiny, pressed in plug. I was able to knock it out with a screw driver...