David, I've had this seal off when I refinished my quarterlight alloy bits in satin black. I can't say if this is possible without removing the quarterlight, but I can tell you that the quarterlight can be removed without taking out the main glass or window mechanism. I can also tell you that the seal top corner is secured by the quarterlight frame screws so don't try to pull it off!!!!!!
If you want specific instructions about quarterlight removal or to discuss the seal further, please feel free to e mail me on
mbw032@msn.com and I can send you pictures and instructions.
good luck ,Martin