Series E 50 disassembly troubles

[j-dogg]

I've got it down to the front outer elements but need to loosen that small retainer ring on the back to clean between the elements is 70% isopropyl alcohol enough to dissolve the adhesive?

 

[j-dogg]

Nevermind, small bit of hydrogen peroxide down the threads got it, but posting anyway and leaving this up for future users to search what I used.

 

[shutterfinger]

Acetone is usually used to dissolve the thread sealer used during assembly.