differences in frames 40 chevy to 48?

1940 is different than 1941 through1948 but would it make any sense to fit my 40 heidts welded/equiped frame under my 41 2 dr sedan? Or maybe splice the frames somewhe
My other thought was to use a 1946 frame if they are identical build my rolling chassis from cutting the $2800.00 of new parts that's were with the 40. This way i canenjoy my 41 this year while building the new chassis.