Don't worry about the roll bar on the rear , the 69s were'nt set up for these so in order to fit one you'll have to weld brackets to the rear axle case , not really necessary.
If you've got the time & tools then change out all the bushings front & rear , I prefer the rubber bushings all round except on the rear spring shackle whereby i use poly bushings.
Ditch the rear air shocks as all these will do is give a hard ride & damage the rear shock mounts , the only reason these are fitted is either rear springs are shagged or enhanced rear ride height
Setting up for the track is a different kettle of fish.
