Usually on a Road King tank I will lay a line right down the
center. I use 1/16" tape for this. Finding the center
of the R-K tank can be deceiving since H-D overlaps the two
tank halves, thus making the dash mount look off center…sometimes
it is though 🙂

 

Now I use 1/4" masking tape to mark as far inside as
I want my flames to go.

 

Now I do the otherside. Both 1/4" tape lines should be
equal distance from the center line. Be sure these are wider
than the stock dash.

 

Since I start my flames toward the top of the tank, I remove
the upper section of the tape. No big deal if you get both
sides the same, but it's a good idea just to get them close.

 

Now I use what I call a "marker" that I lay down
before I do the left side. This will give me an idea of where
I need to bring the inner most part of the flame to match
the other side. This is where your 1/4" markers come
into play. You want to get them as close to symmetrical as
possible.

 

 

For the left side, I lay another longer marker going straight
across over to the left side. I usually leave about an 1/8"
above the right oval so when I do the left oval, I know I
have to come within 1/8" to match the other side.
 

Then I complete my right side, then go back and match the left side.

Using markers helps you lay flames without having to refer
back to the other side while you are actually laying the tape
out.