Hey Brendon. Be prepared to be shocked by the price of F1 decals. I found this out the hard way when I went looking for Ferrari F1 decals for my racing Macchi. What I've done is bought a whole heap generic of sponsor decals of varying sizes. That way you can get the correct size markings you're after for the plane instead of getting an expensive F1 sheet only to find out that they don't fit. Ebay and BNA are your friends for this. Have a poke through my racing Macchi WIP to see what I mean
http://airliner-civil-aircraft-modeller.com/forum/viewtopic.php?f=13&t=607As for entering it in expo, it can go in the new civvie category no dramas mate:)
I've just acquired some JPS BMW decals for this one