the 116 is
easy but requires a lot of interior disassembly to actually get to the easy part. You'll probably want a fresh set of the black plastic plugs that hold the rear part of the liner to the roof just in front of the rear window...the others will get ratty after you pull them out.
Slide rails on the sunroof also need to be removed and where the headliner folds over should be glued. You'll also see old glue marks around the roof and side areas where you should also headliner glue up the fabric. Since it's all covered up by interior finish pieces any minor mistakes are hidden, particularly with gluing.
Be VERY careful when installing the finish pieces back in, particularly the rear headpiece. It's a mega PITA to get back in with all 4 metal tabs slotted into the roof. Probably easiest with 2 people doing the job. The risk here is slipping, etc and ripping the headliner..which is easy since it's generally so old.
Keep track of the order in which you disassemble the finish pieces around the headliner...order of assembly is a real jigsaw puzzle if you don't....heck.it is a puzzle no matter what. i think it should be relatively straight forward since you shouldn't have to touch the pieces around the dash.
I just did a full interior swap and there was about 3 weeks between taking apart and reinstalling....had to start over a few of the reassembly steps.
I wish I had photos but I was rushed and by myself.