technology meets vintage

It seems the latest craze in street rodding is to put a T-5 manual 5-speed overdrive transmission behind a vintage motor. I must admit I don't see the sense to it. My 48' drivetrain is almost stock with just the addition of a newer (1953) stovebolt 6. The motor has two carbs and split exhaust. The original torque tube 4:11 rear end still runs sweet, the original knee-action shocks I rebuilt still work, and the vacuum shift is hanging in there. Why in God's name would I rip all this out? I know I could sell the old parts to finance the new, and yes I do all the work on our vehicles myself. Our 40' sedan street rod, small block Chevy, Turbo 400, 3:88 rear gears gets 10 mpg. My pick-up gets 15mpg. My 48' gets 18mpg. Not bad for a lead sled that's been nosed and decked, frenched head and taillights, lowered, smoothed and running a modified 6 with 4:11 rear gears. Sorry, but for 2 extra gears I'll keep what I'm running. Sure you'd wax my 48' in a race, but for cruisin' I've got just as much smile power.