Bob,
  I'm not sure whether your question is about how to access and attack that
bolt or about it being very difficult to turn.
You need the proper metric hex bit to fit the socket head bolt.  Then two
3/8 drive 6" extensions and a rachet should work.  Or perhaps a breaker bar
with optional pipe for more torque.  Be sure that there is no debris in the
head of the bolt; the bit must be in all the way.  I believe that in some
cases I have found myself below the trans with one arm coming up on one
side to pull on the rachet handle and the other arm on the other side to
brace the rachet head.

Rather than getting a rebuilt starter from a FLAPS, I would recommend
taking your present starter to a reputable shop for rebuilding if you can
find one.  I did that about 10 years ago and that starter is still working
fine without a relay, lately cranking a Subaru engine.

In general, I am in favor of the relay upgrade and have installed them in
'76, '80, and '84 model VW vans.  I have not done so yet in my '91 AT
because of the possible interference with the cruise control.  I have seen
some posts from Mark Drillock that indicate that it can be a problem.  The
related circuitry in the Bentley is very "interesting".

Good luck,
Larry A.

On Sat, Dec 5, 2015 at 2:54 PM, Robert Clemmer <n51219@comcast.net> wrote:

> For several years now, occasionally my starter on my 91 2.1 automatic would
> not start.  A light tap with a hammer and all is well.  I'm getting ready
> to
> head south after Christmas so I wanted to fix this before I'm stranded in a
> rest area with a no start condition.  My challenge is the top bolt/crown
> bolt on the starter that goes through the bell housing into the engine
> case.
> Any words of advice before I break this thing off and I have a real
> problem.
>
>
>
> Thanks Bob C
>