if the rust has started and got a hold of the chassis rail anywehre near the underneath of the rear seats then you would really have to think long and hard before making a dscision

i've got pics at home where a saph that i bought was great up until the rear seats, and fine past the middle of the rear wheel arches too
but the bits in the middle were so full ofholes it make swiss cheese jealous, no word of a lie i peeled the rust back to revlea a hole big enogh to put my fist through on the chassis rail

no wonder the handling was a bit "floaty"