I asked about light seals more generically here in the past but now have a more specific question.

I recently picked up an Autocord in need of light seal replacement. The first roll, shot in low light, looked good. Two roll on a bright day had rather significant leaks.

Upon looking at the seals on the back door, the reason is totally obvious - there is a scattered combination of yarn and felt throughout with some areas lacking anything.

I could easily try throwing some strips of foam down but don't have a good way to know what the seals are suppose to look like (bottom of the groove vs side, seal along the hinge - I have none but I assume there should be something?, what size foam is correct?

Where do people get info on what seals ought to look like or do people just guess and check?