I already have the decals for the 1/144th scale 737-300 kit. here And there is a really good 737-500 paper model available in 1/48th scale. It will take some working out to make the correct fuselage plugs to extend the body front & aft of the wings. as i will only have space to make one of these, the only scheme worth doing is the simpons, xtracolor here in the UK even do the correct paint.
If i get the time after Christmas, instead of using paper i will make this out of the same aluminum used in beer cans
It will be the first time i will have attempted anything like this, so i hope it all goes well