the plastic legs which came with my bath do not appear to fit - following instructions, they don\\\'t sit flat on the floor and there is very much movement, and one looks cracked. my question - is, is there any reason why i should not use the legs and frame from the old plastic bath with a steel bath? the new bath does not have a flat bottom. so i was thinking of hanging it on the old frame, filling the tub, then glueing the plastic feet in for extra support. any suggestions? tell me i\\\'m a fool - i can take it!