I just finished a 38 Buick 7 bow. A few tips for you. Do you have a good pattern to go off of? If so, cut apart and use it to make your new headliner . If not, it get's a bit tricky but still doable. I didn't have a pattern for the Buick so here's what I did. First make sure all bows are firmly in place. Lay out diagram on paper of all bows. I ran masking tape down the length in center and then at 1 foot, 1 foot , 6", 6"and 4" if there is room left. Starting at front, take measurement between bows at each tape mark. Transfer these onto your paper. This gives you the amount of curvature there is as the sections curve inward at the outside edged. Hope that makes sense. When transferring these measurements onto your material, allow 1/4" each edge for sewing. I sew each piece with the headliner listing under it and about 3/4" sticking out the edge. This allows for the headliner to suspend when installed and gives room for adjustment when stretched in place. Don't forget to install windlace on door jams first. When installing headliner. start at rear and work forward installing bows. Next, attach rear center and then pull snug and attach front center. Keep alternating a little at a time until headliner is tight and then start attaching sides, working from center of car and alternating both ways. This is only a general idea. Sometimes it's not enough info but you can get the point of procedure. I usually allow 1 day to make up and install headliner after all moldings are removed and car is prepped for install. Allow extra time if doing the windlace too.
1. center all the bows
2. cut a hole in the listing to allow the bows to protrude
3. Put it in the car and work the seams first, trim back the listing side to side until seams are tight.
4. Pull front to back then into the corners.
I can do most 60's cars in 3 to 4 hours. A 53 Chevy with 8 bows took me two days. Making patterns...sailpanels...insulation...not to mention sunvisors, all take extra time. Hope this helps.