[BurgundyJudge]

I'm in the process of installing a new trunk floor in my 70 GTO. I need to install a complete floor with the braces. A 70 trunk floor is not reproduced.

I have read a 68/69 floor will work but needs to be trimmed at the tail panel because the contour of the 68/69 floor are different from the 70.

I have also read that a 70 Chevelle floor would work too and it has the correct contour as the 70 GTO floor. I'm not sure if the rear cross brace on the 70 Chevelle floor is the same as the 70 GTO rear cross brace.

If anyone has replace a complete 70 GT floor,any advice would be appreciated.

[gtojeff1967]

I used the chevelle pan in my friends car and have one for my car, it is the most closely looking pan if you look at he hump under the speaker tray. the rear cross piece is differant if you can use yours that would be the best but on his i used half of his and half of the chevelle one to make one and weld and take outside to grind all the weld down so it looked like something plus the bumper hides it too.

[BurgundyJudge]

Thanks for the response. The cross brace on my 70 is shot. I have a 68/69 trunk floor I can use the cross brace from and get a Chevelle floor and switch the cross brace.

[3 Chiefs]

Originally Posted by BurgundyJudge

Thanks for the response. The cross brace on my 70 is shot. I have a 68/69 trunk floor I can use the cross brace from and get a Chevelle floor and switch the cross brace.

I used a AMD 1970 Chevelle one piece trunk pan in my 1970 GTO. It looks the same as the GTO. All the braces are welded in. As you follow the flat trunk floor back to the rear of the vehicle the trunk floor starts to angle up. Here is where the difference starts and you will cut the new floor, There is a unique stamping in the sheet metal. The Chevelle has its own design here as does the GTO. I drilled out some spot welds and then cut straight across the pan. After you cut your Pontiac trunk floor the new one will fit nice from the bottom. The one piece pan will not fit through the trunk opening and must be installed from the bottom, body off the frame.
This is the piece that you would cut off the Chevelle floor pan if you use it on your GTO/LeMans.

[BurgundyJudge]

I appreciate that. Looks like I'm getting a 70 Chevelle trunk floor. I was hoping the 70 Chevelle cross brace would be the same as the GTO but they have different mounting holes for bumper brackets.

[gtojeff1967]

I cut that brace diagonally and made it work a lot of cutting and welding and whole lot of grinding.

[BurgundyJudge]

With the number of 70/71 GTOs and Lemans built, I expected more reproduction sheetmetal to be available- at least trunk floors and door skins. Almost anything for a 70 Chevelle or 68/69 GTO/Lemans is available.

[BurgundyJudge]

I was planning on cutting the rear crossbrace from the 68/69 floor and welding it to the 70 Chevelle floor. Turns out the Dynacorn 68/69 trunk floor rear crossbrace does not have the welded nuts for attaching the bumper brackets. I'll probably get an AMD 70 Chevelle trunk floor since it has the correct contour and ribbing for a 70 GTO and figure out how to accommodate the bumper brackets. I contacted AMD Installation Center to see how they install 70 GTO trunk floor and the response was they did one and won't do it again.

[BurgundyJudge]

Update: The Chevelle floor will need the 70-72 rear cross brace grafted to it as the rear cross brace for the Chevelle has different contours that would prevent the GTO bumper brackets from being installed. Since my GTO's rear cross brace is rusted out, that isn't an option. I ended up buying a 72 Lemans donor with a perfect trunk floor.

[BB70]

You hit a home run finding a good donor. Have fun !

['ol Pinion head]

Originally Posted by BurgundyJudge

Update: The Chevelle floor will need the 70-72 rear cross brace grafted to it as the rear cross brace for the Chevelle has different contours that would prevent the GTO bumper brackets from being installed. Since my GTO's rear cross brace is rusted out, that isn't an option. I ended up buying a 72 Lemans donor with a perfect trunk floor.

Customer went through that recently on a '70 GTO. Cheaped out & went w 3 piece trunk floor (bad deal). Thankfully, the triangulated stamped steel rear structure was super solid in his car.