I have bought an Allison go kart to match my dune buggy and going to restore it.  It is complete except for engine. Would you resore it originally or modify the frame with new components?  I am old school and leaning towards not changing anything but motor but want other opinions.  Thanks Jim

For show or Go?    Original and show, making sure it is safe to go.   
Go, make sure whoever drives it is safe as possible, as long as outside is same, most people will not know.
My 1/5th of a dimes opinion.