Marshall JTM 60 choke advice!

[the rake]

First post here so forgive if I've missed this answer somewhere ... I'm looking to add a choke to my old faithful JTM 60. I know these don't always have the best reputation but mine has been solid for many years. I've recently replaced the OT with a Mercury Magnetics one and it sounds good. I also purchased a ToneClone MC10H choke. Problem is, I can't find where exactly I would add this to the amp. I have the schematics so if anyone could point me in the right direction I would be really appreciative. Thanks!