Welcome, There arnt that many differences between the Spec V & standard GTR. Aoshima & Fujimi both do very good versions of the Spec V. Main difference is Carbon Fibre, wheels , Front & Back Seats & exhaust tips.
Cant wait to see what your colour looks like, I have a bottle of Zero paints Midnight Purple III for the Spec V, its a beautiful deep purple but does lack the Gold pearl.
Cant wait to see more!!