First off let me say that I have never heard of nor seen T6's, but if they do make them they cannot fit the endcaps of t8's, the t number reffers to 1/8th of an inch in diameter, so a t5 is a 5/8ths diameter tube, a t8 is a 1" diameter, a t12 is 1.5". The thiner you go the more efficiently light is produced, and with the right selection of phosphors you can get very good output of light with little heat.
You will need a balast that can handle the wattage, and you will need it to be an electric balast with an appropriate starter, you will also need endcaps of the right size to connect the lamps to the ballast, they will need to be the right sized endcaps for youyr tubes, the simplest method is to go out and buy either a light fixture or retrofit kit. Do not buy strip lighting from a hardware store unless you want really dim lighting that more or less exactly fails to please the eye.
HTH