Post Hole Problem

I have been tinkering with a non Pitbull kit and discovering the less than stellar accuracy of the holes that were predrilled.
I have a problem with the post holes - the bridge has the centre of its holes 74mm apart. The post holes were drilled at 70mm. And the post holes in the body are 11mm wide. No available dowel fits - either too large or too small. Inserting dowel would require drilling due to the odd size of the holes.
As you can see from the photo I have already stained and coated the body so I am looking for the least damaging option. (I know I should have checked before I started but I made the mistake of assuming the holes for bridge post would be the right distance apart.)

As the anchors have a lip on them I am planning on enlarging the holes slightly in one direction and then gluing in hardwood match sticks on one side to provide a base for the anchors to grip. The anchor lips should cover the match sticks and it minimises any potential damage to the surface.
Can anyone see any potential problems with this?

Thanks for your comments. Photo attached below. (Only Pitbull for me from now on!)

I assume from the square rear rout its got a Jazzmaster/Jaguar style trem. So what is the bridge style? Is it a TOM, (fixed or roller saddles) or a Mustang/Jazzmaster style?

If you can get hold of 12mm dowel, you should be able to fit that in a standard drill chuck and simply sand it until it's 11mm diameter (or fits in the hole). A proper plug will be more secure than enlarging what you've got and plugging with matches. I've done that before successfully (using slightly smaller dowel). The real Mustang-style bridges have 73mm post hole diameters but only 6mm wide inserts, so if you can get a copy bridge cheaply, then that may be an easier fix as you should find that the hole centres mean that you only have to drill a 9mm hole for the fixing posts, which with 73mm between centres, means new holes in the dowel only go outside the dowel by 0.5mm on each side.

If it was mine i would go to Bunnings grab a 13mm round dowel (actually 12.5mm) cut a bit off put it in a drill and sand it to fit glue it in pretty easy fix scratch plate holes I always use matches and glue them in

Thanks to both of you for the info.
Sanding the dowel sounds like the way to go.
I always stop before charging in, and I also realised that I should check the alignment of the bridge.
The Mustang posts might also solve my problem. I will try those as well.

A quick follow up after getting your help.
That is neat trick with the dowel in the drill. Worked like a dream. Thanks to both of you for that.
I picked up a Mustang bridge and smaller posts on eBay. Did the trick and hardly any dowel visible. Touched it up with a little stain and it sits under the posts. Thanks for the help on that one Simon.

No problem. Glad it worked!