if you're hitting it with 200 out of the hole on a 28" and making decent power with the 408 you will be fine. My 85 had a 'glide in it built by Rob @ Fordspeed, converter stalled about 4000 (roughly) and I had a 3.90 gear and a 28" tire. Would cut 1.35 60' times all day long. We bumped the bottle and it cut 1.29 and was one hell of a ride (stock susp)..
enjoy..
(man do I miss my car..)