Hi, I have a 1979 P200E kitted with a 221 Malossi and blew an unglued (Loctite 938) Corteco blue crank seal.

Anyone had better success with the new Malossi 62mm (not 62.1mm) metal seal in an old Vespa (grooved) from SIP as they suggest its an upgrade to the blue one, also going to use with Loctite 938 this time, but which one?
Thanks