Oh Boy!
I am slowly working on a birthday gift from last year from my boy! It is the original Version of the Motorized version of the See-Through Mustang kit from MONOGRAM! I have always liked this, just never bought it! Now, I have built it's Plainer sister ship many times for the pleasure of it and given as gifts to friends who cannot build models. That larger scale seems to impress and please them!
There are places that for the sake of scale that MUST be built with frames showing, such as the Wings and Rear Fuselage! I have been experimenting with different metallic paints and certain steps to obliterate the flat sections at the leading and trailing edges so there isn't a clear edge all around the back section of the wings.
Well, quite by accident I found a method that works. I Don't recommend this, but, it's funny it even worked. I carefully sanded the inside of the wing surfaces with 12,000 grit till I got a nice thin edge, Polished back to the gloss on the plastic.Then Rubbed a small section of Steel Model Railroad Track over the area like a pencil from the leading to trailing edges right up to the Flap and Airleron locations. It leaves a small line similar to the metal edge of the Frame.
The funny part? Glue does not seem to disturb it and so you can put plastic frames right over the lines without dissolving the line and having bare white plastic showing, IF you don't put too much on there! Also in many areas you can use this for the simple frame thus leaving all kinds of room for greeblie and chotschke installation!
Because of this I can now in the same fashion create inner frames that are translucent for other clear sided models too! Even including See through Car areas! I really don't know why. Maybe the rail piece I am using is not really steel? But something that acts like Graphite on certain types of clear plastic? It will NOT work on Model Car clear parts, so, go figure!