OK Kyle, heres some detail on what you are going to be up against should you decide to do the job yourself!!
First, knowing that you will be pulling the motor to freshen that up, that will leave you a lot of good access to drill out the spotwelds. I would also pull the drivers side fender and splash shields for clear access from both sides. You will also be releiving the torque on the torsion bars to drop the K-frame for the replacement. I also know that you will be replacing the carpet so you may as well just take that out for clear access to the spotwelds in the floor. Now for some pics...
You can see in the pic of this 65 that I have that I have the spotwelds marked with a black dot. There are about a dozen along the bottom of the inner fender where it meets the framerail and up the shock tower. There are also 2 or 3 from each side at the radiator support. You will be center punching and drilling these out with a spotweld cutter.
There is also a gusset in the wheelwell area that needs to be either cut around on the bad side and cleaned up on the gusset or carefully chiseled off of the frame. You will also be chiseling the union between the torsion bar crossmember and the framerail, so get yourself a decent all steel chisel to drive between the flange and the X-member.
Now, there are also about a dozen soptwelds in the interior that mount the floorpan to the framerail. 6 of them go right into the lip of the framerail, and the other 6 go into the doubled up plate on top of the framerail where is starts to make it's ascent up and uner the firewall. In the pic provided you can see that the doubled up plate on this drivers side is rusty and needs to be cut out and patched in with clean metal, a pretty easy job.
The car needs to be sitting on level ground, preferably in a garage, for this process. You will need to support the car on the other framerails, and in the case of your drivers side, supported under the rocker preferably by the torsion bar crossmember. You want to get it good and solid on the ground and not rocking on the jackstands, and then take a few accurate measurments from your old framerail to the ground. Mark where the measurement was taken on the ground with a piece of tape and write the measurement right on the tape. Mark where the framerail meets the torsion bar crossmember and start removing it
Reassembling with the new framerail is pretty straightforward. Getting it to your marks and tacking it off, checking your measurments and making sure all the panels are tight before filling the spotweld holes, typical replacement stuff.
This job is not that hard and can be done by yourself provided that you have a few of the right tools, a spotweld cutter, and welder to weld the new frame in, and some air tools such as a die grinder. I think with some help in your corner you can pull this off and have that framerail replaced in a weekend or 2. Geof
