I thought about doing this to one, to get an economical daily driver, but I have not gottet to it yet. I do have a spare 2.3 efi and a matching T5 setup laying around.
That 351 should absolutely haul faster than that. My 5.0 82 car does 8.2 eighth miles on motor and 7.80's on a 100 shot with just a 90,000 mile 1968 302. I would be thinking the 351 would have low 7 or high 6 eigth mile potential very easily.