I need help with adjustable leed out guide

I looked up plans, and hopefully found the correct ones.  It is just a comb.  Combs are diffi9cult, even in plywood.  The teeth require stable material, so the wood needs to be best quality.  

Pilot drilling then carefully sawing to the pilot may be a good choice.

I would consider plastic or aluminum if the plywood you can obtain is not stable enough.  A hardwood part glue stabilized may also work well.  

I also wonder about your tools, this cannot be made easily with a knife, the wood gets pushed too much as knives normally deflect the material as they cut.  A bench pin and coping or jewler saw, or a scroll saw are rather required.  If you have to use a knife then dragging the sharpened back of the point like a single tooth saw is the way to go.

Or coroplast like New222 suggested.

Phil

If this way is thought of, what I would do is teh following. Give it a quick sanding with a scotch-brite pad or equivalent, followed by a quick 'flashing' with a lighter/torch, etc. Then glue it to whatever using your favorite epoxy or CA glue. The above instructions are for the coroplast.. However, if the wing itself is painted, I would also give it a quick sanding using the Scotch-Brite pad also before gluing for the best adhesion. The wing however, would not need to be 'flashed'.

Check this out Chevyiron420 https://stunthanger.com/smf/building-techniques/adjustable-leadouts-pictures/