> I have found good souls
>who will stand behind their work, even after the warantee has run out.

Unfortunately there are two sides to this.

Many years ago I bought a '65 bus, put a used engine in it, fixed a
number of smaller things (brakes, electrical, 2 tires), and sold it
to a stranger, giving her a 30-day warranty on the entire car. In
ensuing weeks , she told me she was quite happy with it.

Six months later, the engine spun a bearing. I swapped it for another
used one (both 1600 SPs), no charge. Two weeks later she sued me, on
the grounds that my after-warrantee service was evidence that I secretly
knew I had sold her junk.

The judge threw out the suit, but I learned my lesson, and haven't given
warranties on any used items since. In fact, haven't bought cars for
purposes of resale since. Life's too short.

Fortunately, people like that are pretty rare. But surely, shops that do
large volume, even solid honest ones like you describe, must encounter
them, and the shops are sitting ducks for this kind of thing, rare though
it may be (I hope).

Your case may be a little different, since it involves an engine rebuilt
with new parts, still inside its warrantee period(?), but without
paperwork etc. But if they don't want to do warrantee work without a
provable warrantee, don't be too hard on them-- if they've been at this
business for any length of time, they may have good reason to be skittish,
no matter how honest they are.
    _______
   /\ o o o\         Steve Maher   smaher@gi.com   75461,1717
  /o \ o o o\_______   San Diego, California
 <    >------>   o /|
  \ o/  o   /_____/o|      '80 VW V6anagon
   \/______/     |oo|        '66 Mustang Coupevertible
         |   o   |o/       '89 Son Sherwin
         |_______|/
                       http://www.wp.com/IrishMafia