Most floor shift conversions for 3 speed transmissions put the shift stick in an awkward position and require you to butcher up the floor pan pretty badly. Unless you do some creative fabrication to the shift lever, you'll usually end up with the stick tight against the front of the seat cushion, making 1st. and 3rd. gear hard to engage without modifying the bench seat or installing bucket seats. Try to find a good condition Hurst Dual Pattern shifter at a flea market or a swap meet. Some of the shifters produced by Mr. Gasket or some of the overseas copycats are pure junk, and they'll make you wish you had you're moderately flaky column shift back. Considering the cost and hassle involved, I'd recommend rebuilding the original shift linkage.
Jerry

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