1/4 mile is probably doable with that 5.86 depending on where he liked to run that engine and the tire height he used.
Friend of mine runs his X33 Z with 5.38's, a 28" tire, he runs a nash 5 speed with a 3.19 first gear and 1:1 fifth. He leaves at 7,000, shifts at 8,000 and runs through the traps at 8100, usually 128mph or so and goes 10.60's, and a 1.39 60 foot.
A 5.86 gear would only bump the finish line rpm about 6-700 rpm. Squeeze a 29" tire in there and knock it down 2-300 rpm. So it's doable if it's making power up there, but you need good parts inside if you want reliable.
PS. I agree janobyte, I'd have some fun with it as is, and track passes wouldn't be out of the question.