I am conscious of not wanting to be seen to be grandma demonstrating egg sucking, but then again I have often seen others guides and thought "I would have never have guessed that..." , so my guides are posted in that spirit....
First cut some nylon bristles from an ordinary hand brush, (don't tell the wife....
),cut to length, and some sprue end pieces. This is from a Revell Leopard 1A5.... 
Cut the bristles to length, and place the sprue pieces in plasticine or blutak.....
Drill out with a suitably small enough drill bit and glue the nylon bristle in with superglue.....
Cut the base off the sprue piece and glue onto the model as desired. If you need to glue onto the side of a 251 for example, just cut the sprue at the appropriate angle and glue on.
