1st or 2nd from top - part no. 27170/69 - should be fine.
alfa specs include:
*12mm diameter
*1.25mm thread pitch
*60 degree taper/cone
*~25mm thread/shaft length
note, there is a link to an application guide on that site. it lists alfa specs. the specific recommendation is not listed on the Specials page: 27216, 24.1mm shaft length
BUT, i suggest you remove a bolt from the car and measure the shaft length to be sure. the GTA may be different; my GT has a shaft length of around 30mm.
