When I finished my BA at UCLA in the winter quarter of 1970, my draft status was immediately changed to I-A.  With the low number in the lottery, I was not surprised to receive a notice to appear for a pre-induction evaluation at a federal building somewhere on Wilshire Blvd. east of Beverly Hills.

The site was staffed by Navy personnel who directed us through a number of standard tests that would be administered to anyone during the course of a medical check-up.  One guy fainted when they were drawing his blood. There was another guy in our group who chose to dress in some kind of costume and act as if he had psychological issues but his act was so transparent that I find it hard to believe it affected his fate in any way.  
I found the psychological and intelligence tests interesting.  They required the test taker to solve spatial and logical problems in a set time.  I had no trouble with them and finished early.
When all was said and done, I received a I-Y deferment since my weight at the time of the test was 280 lbs.  The accompanying letter said that I would be ordered to report for re-evaluation at a later date–a date that never came.  The following year I was classified as IV-F without any further testing.