cutting contours to fit trunk panels?

ok i been trying to cut the contours of the trunk walls for a trim panel to fit perfectly and cant seem to get it no matter what i try. i use cardboard/ posterboard templates . tried measuring suing a flexible ruler to take the shape but i guess when i take it out and trace it the thing must move. anyone have tips tricks or a site with pics to help me out here be fore i go nuts thanks

have you tried using a "contour gauge" yet? thats what i always use.

yep. its such a tigh spot that its hard to get in there to be acurate. it on a 2000 civic hatchback. unless im a big spaz lol. what else can i do

use spray adhesive and spray the area you want contoured. then,  place butcher paper, not wax paper,(butcher paper is normal on one side and has a waxy surface on the other side and is thicker than wax paper) to the surface you glued with the paper side on the glue and the waxy side out and press it all down as good as possible an get out all the wrinkles as good as you can. then use your original method with the cardboard and cut your shape. place the piece of wood you made from the cardboard template from up against and fasten or hold it where you want it. then between the wood and the butcher paper fill in the gaps with either body filler or expandible foam, which ever you prefer, i use the foam. after its dry, remove the wood and the paper and sand the foam or body filler down so that it is the same plane as the wood. then fiberglass and sand your piece as normal. when finished, you should have a piece that matches and fits the countor perfectly.