I think they should stay pre-48. if you change it will ruin the shows...Look what happened to the 55-57 Chevy people when they started letting any year chevy in the shows. The shows were a disaster. I know I want to see 55-57 when I went to the shows, not a mass gaggle of all years. They have other show for the mass gaggle type people.
Oh and you can still find some old iron for good prices..I have a 34 ford tu-door sedan that I picked up for 5 grand. It is apart and needs some work but the body is unchopped and original so i can cut that sucker any way i want. Jmo Tim