5.9 Magnum Drag racing

I am finishing up a 5.9 swap in my stock 74 dart. It will be a street car that I will drag race when I can (about 5-8 times a summer). By stock I mean everything is stock but the swapped in 5.9 magnum. It has the air gap intake on it and a 750 willys 4 barrel carb. 2.90 gears and a stock 904 trans with a small stall convertor in it. What do you think it will run in a 1/8th or even a 1/4? For those of you who have drag raced your magnum swaps what kind of times do they run? I am looking at bolting in a sure grip but wanted to put in a set of 3.55 gears too. Swapping in the gears though scares me a bit because of having to set them up.