IMO the V6 mustang have now is still fast. Ive hit 136 with it so far (which I know isnt fast) but it cruises well at 110 which is decent for a v6. The 0-60 being ~6 seconds sucks but in upstate ny and nyc that doesnt really matter. Im not a pure racer. Im only trying to get an older 99-04 gt because i like style better. 
and it will put more $$ in my pocket…
I figure selling my mustang for 10k and getting an older gt for 4.5k will give me 5.5k on the side AND give me a car that I like lol. isnt that a good trade off?
Do you really think that a 2000gt mustang will cost A LOT in upkeep and repairs? I feel like its still pretty reliable… I feel like my 07 mustang has caused too many problems strictly because of the year it was made.