Just Do It.
Nevermind the 1/4 mile time, the swap is 1 of the best things you can do for your 5 speed. I did it and it was like driving a totally different car. You will get to use 5th gear on the freeway going up steep hills, cruise around the city in 3rd w/o bogging the engine or going back to 2nd. If you have good rubber, it will jump off the line.