those pesky nose bolts, now locate guide rail.

[Gerald Cousins]

Fenton,
Used several of the various techniques mentioned for many moons.  Mr G's method is my (current) preferred however I use ball bearings (steel) rather than BB's.
Easy to retrieve with a rare earth magnet from an old hard drive Making sure there are no remainders in the holes to muck up a drill bit or screw.
Hopefully you are also using a story stick or similar marking/recording method. Always helpful as memory shortens with age. =) 
With DGR's usually they clean up well with a light sanding and such and just need rebushing. Is there a specific reason you're remfng? Damaged? Split out? Warped? Not enough work? Just curious as to the decision process. I only recall 1 or 2 times having to remfgr. the DGR. One for a Knabe player he other for a MH.  Used the original as a template and at that time located the holes with rounded off drill rod and the same technique as below. 
Gerry Cousins, RPT
PS Since you mentioned " As long as we are locating things...."   Has anyone seen my marbles ? Nick Gravagne, RPT wrote:
<Do not plug the original DGR holes in the belly bar. Now place the 5 or 6
<BBs in the DGR holes and light tap them down to seat(or use 1 BB at a time
<and move to next hole), set your board over top and either with the side of
<your fist, or else a small dead blow and block of wood, strike down on the
<soundboard top over the area of the BBs. Upon removing the board find the
<small indents and drill through from bottom to top with a 1/8" brad point
<(usually the right size). Don't worry about EMC unless for some reason the
<board is extreme one way or another (which it shouldn't be anyway).
Fenton wrote:
<As long as we are locating things, how about some ideas on locating the 
<damper guide rail. 
<My last job I pluged the holes, made a new rail and started over. I've 
<frustrated myself trying to exactly locate the little number 8 screws, or 
<whatever they are, drilling precisely in the right spot through the new 
<soundboard, to catch the old hole. 
<Tips, techniques? 
<Thank you, 
<Fenton  
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