You will need a spring compresser, and a bfh to separate the ball joint from the spindle. Jack the car up on that side, remove the tire, place a jack stand under the car to support it. remove the shock absorber, compress the spring, separate the upper ball joint from the spindle. then unbolt the control arm from the shock tower ( if you have a big block car with headers, this is REAL fun) Be sure to replace the spring saddle too along with new spring insulators. If all your front end parts ar ethe original. then now's the time to replace everything, noit just one piece at a time.
I believe the bushings unscrew from the shaft, then pull the shaft out. I would recommend that you change the whole arm, the old ones get weak with age and are prone to bend. Ditto with all the other original parts.
Honestly your best bet is to replace them as was mentioned before. By the time you get the bushings out you will probably find the threads in the control arm have disappeared and you will have to weld the new bushings in. If you must remove them then an impact gun and/or a long breaker bar and a big vise, these suckers are in there tight. If you have alook at the grease fittings and unless you have a 90 degree nipple on there, these have not likely been lubed since manufacturing. That is why replacement is recommended.
I got the old ones out and the threads are fine in the control arm, but my question is how to install the new shaft & bushings ? The shaft has threads and the control arm has threads also. Do you have to thread each cap on at the same time?
The way you are supposed to do it is put one bushing in the control arm torqued down to 35-45 lbs. Put the oring seal inside the bushing then put the shaft in and thread it in all the way in, then put the other bushing in and then they are designed so you can center it by unscrewing the shaft and it should thread into the second bushing. Center it and measure it so it is exact and you should be good.