The easiest, most expensive and most time consuming way is to dismantled the whole car and start from scratch. Restore and paint the body, rebuild the engine, refurbish the suspension and brakes and slowly, carefully reassemble the whole thing with all new rubber, poly and interior parts. (Wick Humble's "How to Restore the Datzun Z" is an indispensible help in this process). However, hardly anybody has the time, space or money to do it that way. I think I probably speak for most people in this forum when I say we do it bit by bit as we can spare the $$. My car has been a work in progress for more than 5 years. Unless I win the Lotto tomorrow, it won't likely be done until about 2011.
Start as best you can to make sure your chassis,floor,frame rails etc etc are good if they are really in bad shape you may not want to tackle that car. Try another Z.
The Chassis is most important because all the good things you do to your car must somehow attach to the chassis see?
I learned the hard way. I did a nice paint job first then did some suspension work. Next I did motor work followed by more suspension work to handle the hp. then finally the interior. ( I changed it from white to black.) Now I have a great motor and a pretty good suspension yet now I'm fighting the rust bug again (2 holes in the floor + rust on the bottom of both doors and finally a rear wing that I added last year that doesn't quite match the old paint) So take take my advice.
Best way if your on a budget and can only do a bit at a time.
I'm currently putting back together my 240Z 72.
I’ve been doing shows & driving it during the nice summer days up here in Canada. It's always been in very good condition but the age & hard driving was starting to show on the structure.
Here are the steps I took for my restoration:
1) Strip the car completly (only the heater was left in)
1a) Identify correctly all the parts you'll be removing, belive me it will make it easier when it's time to put it back together (I used a lot of zip lock bags & peanut butter jars…).
2) Put the car on a rotisserie (a lot easier to work on the floors & wheel wells)
3) Bead or sand Blast the whole car & repair any structural or floor damage (now is the time). Mine was especialy weak in the rails were the sway bar connects, also be sure to verify the windshield post all the way down were the door indges are.
4) Paint Base coat/Clear coat for the body, urethane for under (it will give you a shiny finish & it's more resistant).
5) Assemble with new or very good condition parts, follow your budget…
Extra) I powder coated the suspension components & the engine cross member for look & durability. I also removed the entire interior under coating on the transmission tunel & floors (found some surprizes under there) I will replace it with new technology material.
If you wish to enjoy your Z for another 10 years like I do, put some money were it won’t show but you’ll be greatfull you did in a few years. So much can be done with a nice paint job & fancy wheels.
It was a very enjoyable project for me, I hope you’ll enjoy it as much.