Engine stops when at intersection

[al in oregon]

OK, here goes.

My 1999 F350 7.3 with 101,000 miles has just started shutting down (3 times in this last week) when either I'm stopped at an intersection or when in Park.
After reading the forum, I suspect the camshaft position sensor. If I am correct, is it just a matter of removing the old and replacing with the new or do I also need an alignment tool (I saw this somewhere when searching the net)?

Any other suggestions as to the problem would be very helpfull.

Thank,

Al