Dealing with 70's Bridges
As you probably know, 70's Martin D's often have a mis-placed bridge. There are several solutions for this, presented below. Keep in mind that I can combine options, too. I can scoot the bridge back a little, cut the slot back a little, and put small shims under the heel to correct a really bad misplacement w/out making it looking it ugly.
To cut to the case, I usually prefer Option 2, balanced with a little Option 1.
If the misplacement is less than or about 1/8", I can make a new bridge and scoot the saddle and pins back. When I do this, I like to angle the pin holes to follow the saddle as this looks good and uses the space on top of the bridge better. This is only an option, though, if the misplacement is 1/8" or less. Any more than that and the saddle's going to be sitting in the middle of the bridge.
Move the bridge back to the correct location. This will reveal some bare wood that was under the leading edge of the bridge. Fortunately, there is often some original finish under that will help mitigate this scar. When there's not, I need to deal with the scar; I can usually make it not-real-obvious. It'll never be invisible, but this is where we decide whether cosmetics are more important than function or vice versa.
As you can see, results vary widely from nearly invisible to pretty ugly. However, note the difference between strings-off and strings-on in a few of the pictures.
This a raw scar, unworked on and unfinished. This one's over 1/8" off.
Here's a bad one- nearly 1/4" off and dark, ebony stained wood underneath.
But here's the same guitar with strings on... the scar is much less obvious, I think.
Another shot of the same guitar
An average scar. It's a full 1/4" but is blending in fairly well.
Same guitar with strings on.
Here's one that turned out well. This is about the best you can hope for:
This is an option that I have never actually done, but it is an option, especially if we're doing a neck reset. This option involves using shims to space the entire neck back.
Having never actually done this, I don't have any pictures. What I do have pictures of, though, are necks that I've shimmed out to correct an overset neck.
This is a pretty thick shim:
Shims can be stained black to match binding.
My personal D-28 sports neck shims:
We can replace the entire fingerboard with one with a slightly shorter scale. This is another one I've never done, but John Arnold favors this approach.
Well, there you go. Consider and pick one.