Automatic transmission on the floor

you can gather all the pieces to do a stock floor shifter or get an after market one. the after market ones probably all use a cable instead of linkage. the factory ones are all (as far as i know), used with a center console to cover up the linkage. you can then remove the column shifter handle from the steering column by knocking out the roll pin.
HERE's a bunch of threads to go though, not all on target, but you can get an idea of what's out there.

good luck