Top Fuel Dimensions

I'm currently attempting to build a Top Fuel style Dragster and was wondering what sort of length I should be aiming for. I've glued it all together and it's about 5.5 inches wheel to wheel, does that sound about right or too long?
How does that compare to the old Aurora dragster?

Thanks.

Here's what I've done so far (and please bare in mind I don't have any modelling skills whatsoever)

I took two Tyco Curvehugger chassis' (quite ironic really, using them to go in a straight line ;D)
Removed front wheels, pickups and pickup springs from one and cut off the pointed bit of the guide, leaving the clip bit to hold the front on.
I then removed all the rear end of the second chassis and trimmed the chassis until there was little more than the front end and a flap to use to fasten the extension to.

I then needed to find something to use for the chassis, and as I wanted to use what I had available, i searched the house and found an old DVD case which I cut too fit three pieces and glued them together for strength, then glued them onto the two parts of the chassis.
Next job was to attach the wires and try it out...it goes.
I need different rear rims and tyres but that's a little job for the future, I want to get the cosmetics done first.
The hard part is yet to come getting a body to fit and making/fastening the rear wing.








All this and someone will say I'm way out with the dimensions ;D