I wouldn't think so. Guides for 1/4" tape won't be able to do a very good job keeping 1/8" tape where it belongs, in relation to the heads.
You might do better modding a cassette tape case so that you can feed that 1/8" tape across heads made for that size tape. You could set your Sony machine in front of the cassette machine, for supply and take-up of the open-reel tape. It would be rather a Rube Goldberg setup, but it could work.
Or, maybe you can make some guides for the 1/8" tape, glued onto the guides on the Sony machine. Just use glue that makes 'em easy to remove.
