I'm considering buying a BA ute that is column auto as 3 seats would be handy for the time being but later on if I decide I want to convert it to T-Bar auto, What would be involved? I imagine it would be a big job yeah?

if it is based on any previous models I am sure all you would need is the t-bar connection (elecs and rods) and removing the column mechanism off the column and from the box and simple matter of connecting the t-bar connections on the floor to the box and plug in the loom ( i assume that a loom plug would still be under the carpet.

But you may or may not have to cut a hole out of the floor.