Ring & pinion question ??

[jonabalco]

Once again I am going to ask people who have been there done that !!
I'm currently building a 68 GMC short bed Here's what I have !! I have taken the 305 V6 out and dropped a 4 bolt main 350 about 400 HP I have kept the sm 4speed Muncie tranny it's the tranny where 1st is kind of a granny gear .... The rear gears are currently 3:54 i'm looking to get a little more speed out of it ... Am I better with a set of 3:28 or going with a set of
4:09 gears please let me know any help is GREATLY appreciated !!!