I replaced the roof. i did it because of the tipical rust at the rear and top front. you have to remove the lead at the pillars and the quarters. the drip rails are welded underneath the roof skin. so the rails are welded to the structure and then welded to the roof skin. underneath you will have to remove the weather striping and crome bracket. then grind off the welds or drill them out if you choose to keep the drip rail. i would grind off the roof at the edges and remove the center section of the roof so the work will be a smaller job when taking out the rest. the skin is very flexable so when you get the replacement it would be nice to get a extra set of hands to place it in place. the rails are not hard to replace just keep the dimensions in mind. i cleaned the structure and rust proofed it. the bad part is the repop roofs are not perfect and will nead some reworking. I went with a rust free original roof that i cut out and and cleaned up. it takes more time when you use a good used roof because of the extra work in prep. I know that the 69 roof from a firebird or camero will work on 67 to 68. the bear is finding a good doner. it took me 2 yrs for a local doner. it looks great and worth it. i filled it in with filler at the quarters and no problems so far. good luck