hey i have a 1981 monte carlo i am trying to fix up and make look pretty haha, i have been doing the body work on it but when i reached the rear and removed some rusty sheetmetal, i found that the frame was rusted all the way threw, i was gonna just remove the body from the frame and fix it until i found out it is a unibody, any ideas ??? it would be greatly apretiated! THANKS

 

There's two things you can do. You can find a Monte Carlo and cut out the section you need and weld it, or you can make a custom piece of metal and weld it in there yourself out of angle iron or something to that affect. Figure out how authentic you want it to look and go from there. Make you sure you treat all of that metal because the rust is going to be in some of that metal that is there now. You need to get a metal grinder and grind on all the metal to figure out what just goes away and how much of that is good metal. Then you need to cut out the parts of metal that are eaten up by rust because they'll just cause you more problems a few years down the road.

 

i cant really tell from your pics exactly where your rot is but if its in the frame horns you can purchase them and weld them in. or the better move would be to find a v6 car with a nice body and frame and build off of it. body and frame work is pricey to have done and not worth it unless you yourself are going to do it.

 

unibody???? the 4th gens are bof!!!!

 

g body is last full frame monte made look again could build your self some out of rectangular tubing

 

X2! It is a full frame and not Uni. It may be so rotted that the frame is missing sections. You need to find a G body and go to town on the frame. This kind of work can get expensive in a hurry if done by a shop, as MonteMan stated, but if it isn't aligned right the car can end up funny.

 

That frame is used in four differant cars man. Chevy Monte Carlo, Buick Regal, Pontiac Gr. Prix, and Olds Cutlass.
When my 80 Monte needed a frame I used the frame outta my 86 Regal. It sounds pretty simple but I had to remake all the mount locations on the bottom of the body.

 

but was that due more to the fact that your '80 MC is technically an A-body vs the G-body of the regal? Currious.

 

Donutboy97, Good point! The only thing I found differant was the exterior sheet metal. I had to remake my mount locations because most of them were too rusted to rebolt the body down and some rotted off car. I just had to remake not relocate them.
Im not 100% sure but I thought the A-body ended in 77'. My 78,79,and 80 Monte's all have the same frame as my 84 Gr.Prix. My 86 Regal was the same too.

 

last year for the a body designation is 81. 82 and up is a gbody. i know the malibu frame is 2inches shorter up front. i also thought there was a difference in the cross member bolting locations between a and gbody.