hello lf community.

this is my first post on this forum. i haven't had the time to properly introduce myself yet, therefore just a few words to explain what i am doing. coming from medium format (rz67) i am about to take my first steps in large format.
i have got access to a metal workshop for another month or so, and the skills to work it, mostly aluminium in this case.
for the moment i bought the necessary parts to start building my first lf-camera. i would like to construct a camera that will be convertible into 8x10 later on, but for now i am thinking about 5x7. havent decided if it will be monorail, most likely, as i havent received the bellows yet. its a 23x23cm (inside) straight bellows of about 70cm..

i bought two fidelity deluxe holders. my main concern is the back part, and my question shows that i have no experience in the field yet.

where does the groundglass go, when the film holder is inserted?
i imagine that the gg is held in place (pressed tight against the back) by bent strips of metal, and that the film holder would be pushed in between?
does somebody here have construction plans? hints? what choices are there to be made?

any help is appreciated.

with very kind regards and open ears,
chris