I'm looking to replace a passenger side frame rail and inner fender on a 71 Demon, what am I looking at any tips would be appreciated.
I have metal and welding experience, I have replaced floor pans,trunk floors,quarter panels and spring relocations.

I've done it many times. Drill out the welds in the existing parts you are to remove until the frame rail or inner panel can be removed. The replacement parts grind off the sheet metal opposite the part you want to use, this way you start with a smooth surface on the part. Clamp or hold the replacement part onto the car and puddle weld each of the holes you drilled out on the car. Make sure you measure everything before you remove a part this way you can place everything as it was from the factory. If you do it right nobody can even tell you replaced the parts. If you need more help PM me and I will send you my phone number. Take your time and Good Luck.