Buy the special BSA tool (part # 61-3005) to remove the chromed fork oil seal holders. The BSA tool is basically a hollow tube with two tabs at its base that lock into notches inside the oil seal holders. It is not too expensive and is the best tool for the job.
I unsuccessfully tried a strap wrench and foolishly tried a pipe wrench to remove the oil seal holders. I also tried to make my own version of the BSA tool out of a metal pipe and failed miserably.
If you have a query or information about BSA motorcycles please contact us