I was too stressed out to take photos while I was gluing the weatherstrip in the front door, but with that out of the way, I did take a few photos of gluing the weatherstrip in the engine panel. The 3M weatherstrip adhesive can be a little messy. I taped off the area around where the weatherstrip is is going to be installed.
Weatherstrip adhesive is basically like a contact cement. You need to apply a thin layer to both pieces that are being bonded together, let it dry until it's tacky, and then press your parts together. The problem with using tape to mask off areas is that the adhesive wants to pull off with the tape as you remove it. I had to run a razor along the edge of the tape as I lifted it off.
The new weatherstrip installed after removing the tape. I purchased to correct profile seal from Isettas-R-Us. It's exactly like the original. The back has a small step to accommodate the flange around the edge of the door, and the front is ribbed like the original.
After installing the engine panel I was a little bummed that it does not lay flat against the body. There is about a 1/8" gap on the sides near the middle. I realized that the rubber funnel on the engine that presses against the engine panel is pressing the panel out. Hopefully with time the rubber funnel will flatten and allow the panel to sit flush with the rest of the body. I noticed in old BMW press photos that even the cars used in press photos had this gap, so I'm not going to worry about it too much. On my unrestored red Isetta the engine panel sits completely flush with the body, but I think the reason that it does is because the rubber funnel is completely flattened out with age.