Measuring for boat tail
 

My mirage has a pretty flat square profile at the back (no downward taper of the roof.)
How do I determine the appropriate measurements for a boat tail if theres no downward curve to follow?

is it possible to make it to short or to long?

Yes.

Below is a thread where we discussed installing boattails and has the boattail pattern I used for my car. Make a pattern of the tailcone of that aircraft and paste it onto a photo of a side view of your car. If you don't want to chop into your car's roofline metal, just start the boatail curve at the back end of your car's roof.

http://ecomodder.com/forum/showthrea...x-hf-2609.html

this is very interesting stuff.

I'm thinking this thing is going to be atleast 4ft long. I'd like to make it as rounded as posible like yours is Bas...I like the bent plexi that you used to cover your lights.

I may take a slightly alternative fabrication route because I don't have the tools to do metal work.

The nice thing about the aluminum bar and sheet construction is that it takes a very small and inexpensive tool set to do it. Everything added onto my car has been builrt with the following toolset: jigsaw, cordless drill (and drill bits), heat gun (for heat setting coroplast and lexan), hacksaw, tin snips, 2 large pipe wrenches (for bending aluminum bar), measuring tape, pipe taps, tap holder, box cutter (for cutting coroplast), philips screwdriver, pop rivet gun, paint brush, and caulk gun.