Joe,
I don't know about the door seals, but when I replaced my trunk seal, the old glue looked like contact cement. The weather seal adhesives available at auto parts stores also seem to be contact cement (or at least the directions are the same).
I cleaned all the old glue out and stuck the new trunk seal in without any glue and discovered that it took a fair amount of fiddling around to get it to fit properly. Since contact cement and weatherstrip adhesive grab instantly (if you follow directions) and would prevent any fiddling, I decided not to glue it at all and it seems to be fine.
I imagine you could just brush in contact cement and fit the seal while it's wet and that would give you some time to fiddle it into position before it sets, but do a dry fit first to see how it goes.
Also, after installation, coat the trunk seal contact surfaces (on the seal and the trunk lid) with a silicone lubricant before you close the lid. The seal needs to be able to slide a bit against the trunk lid. If it can't slide it binds, making it very hard to close and distorting the lid.
George Davis
'69 280 SL Euro manual