From Downtown San Diego, take the Martin Luther King, Jr., Freeway (94) east for 7 miles to the Broadway exit in Lemon Grove.
If you're coming from the north or the south, take the 805 to the 94, and then take the 94 east for 4.3 miles to the Broadway exit in Lemon Grove.
Upon exiting onto Broadway, go straight (east) for a few blocks, and then turn right (south) on Massachusetts Avenue, which is clearly labeled with a very large sign
-- as are the following cross streets!
On Massachusetts Avenue, go to the fourth light -- Madera St. -- and make a right (at 45 degrees). Go one long block and make a left on Ramon, then one very short block and make a right on Primera St. 1663 is the second driveway on the left side of Primera. There is plenty of free parking on the street.