In the image below you can see that the body came with a pre-cut hole
for a tremolo system. This hole is made for the standard Fender 6 screw
tremolo system I mentioned in a previous posting. But as luck might
have it, the 2 point Wilkinson tremolo system I like was designed to fit
in this exact same hole and use the same back cavity for the tension
coils.
This image shows the back cavity that will contain the tension coils (springs).
I own 3 guitar routing templates for altering/customizing/destroying guitar bodies. One of these templates is specifically designed for the 2 point Wilkinson tremolo system. You can get similar templates online for free, they are a pdf version that you download and print. I purchased mine from Stewmac online supply store. Stewmac has fantastic supplies for hobbyists (and professionals) that want to mess around with guitar projects.
If you look closely at the template you can see the main tremolo hole and 6 small holes on one side and 2 small holes on the other side. One side of the template is used for the Fender 6 screw tremolo system and the other side is used for the 2 point Wilkinson tremolo system. To avoid any confusion for myself I marked the side I want to work with, with a W and an arrow pointing toward the neck of the guitar.
It is also very important to find the midpoint between the 2 points. This midpoint will fall on the center-line of the guitar. First I scratched a line through the 2 points. Next I marked the midpoint between the 2 points with a Sharpie. Last, I scratched a perpendicular line at that midpoint.
Now I could have just placed the template down and lined it up with the pre-made tremolo hole, marked the two holes I need and be done with it. However I want to double check the template to make sure it is correct. Therefore I need to do some measurements.
I place some drafting tape down on the guitar and began to mark my center-line. I recommend using a laser level to find the center-line, but I used a piece of string that I ran down the center of the neck making sure that the string went through the center of the fret dots (you can see 4 of them in the image below). I made a number of marks on the drafting tape and then...well...connected the dots with a colored pen.
The bridge location is at a distance of 25 1/4 inches (for a stratocaster) from the nut at the top end of the fretboard. I made a mark on my red center-line 25 1/4 inches from the head of the guitar. I then made a perpendicular line at this location. So my guitar center-line is in red and my bridge distance of 25 1/4 inches is marked in green. The 2 posts for the Wilkinson tremolo will be located on the green line.
The moment of truth! Did the template line up? Yes, it did! Spot on! as David Gilmour might say. I used double side tape to hold the template in place and I used a black Sharpie to mark the locations for the 2 post holes.
Things are going very smoothly so far. I removed the template and placed the Wilkinson tremolo in the hole and lined up how the bridge would sit and did some extra checking. I used a piece of string and placed one end in the top groove (low E string) and ran it to the bridge to see if the string would lie on the fretboard. Looks pretty good!
I did the same for the bottom string groove (the high E string) and that looked pretty good as well.
Well everything looks pretty good. I've done multiple measurements so I guess it's time to cut!