The 93-96 TT models (BG5A) featured the EJ20H (260hp) in both auto and manual. Some were fitted with bilsteins most weren\'t. I don\'t think their was an official GT-B model.
In 96 came the facelifted model (BG5B) which received a new look front bumper, projector headlights, 17\'\' alloys, tinted tail lights, better interior etc. The top of the line models fitted with bilsteins were called the GTB. The manual version of the GTB received the new EJ20R motor, the first Legacy to reach the Japanese maximum output of 276hp (206kw). The auto models of the new GTB continued with the older EJ20H motor right through until the end of the production the the BG series.
The Limited model featured a unique front bumper and large spot lights. Their maybe other unique parts added but knowledge isn\'t the best on this model. Reuben may be able to shed some light on this.
Hope that helps.