The location of the canopy tracks is dictated by the location of the slider frame rollers.
I suggest that you place the canopy frame into the position that you want it on the fuselage, with the required (final) inset from the fuselage sides, and then locate the tracks so that they are exactly parallel front to rear, and the rollers slide freely and centred in the tracks.
I positioned the tracks on the sliders using duct tape before drilling any holes.
It is recommended that the front (and rear) canopy frame be initially bent/adjusted so that it is narrower than the desired final width to allow for some "springback" when the plexi is attached - your canopy track location should be to the final position, of course.
Scott McDaniels wrote a useful article about canopy fitting in the RVator 2002 volume 5 which you could usefully refer to.
Bill Brooks
RV-6A
Ottawa, Canada