Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:3127646.
This is a set of tools that will allow you drill for blind fastening and tap the ends of V Slot aluminum (Aluminium) such as that from openbuilds.com.
I needed these while building my FK-1 large format 3D Printer. (https://www.youtube.com/playlist?list=PLoJycTgmGC47H5_A7Fs0giDvwOR5HQZRE)
The bushings I used for these are from Amazon and are available here: https://www.amazon.com/gp/product/B01G8XA51G/ref=as_li_ss_tl?ie=UTF8&psc=1&linkCode=sl1&tag=funking3d09-20&linkId=d94572c17b24b33c8dbe83ded11efe9e&language=en_US (affiliate link) *Note: These should be about $4.50 USD. If they are higher, you might have to wait and let them come back down. I have seen them jump up to $14 USD.
A quick how-to and example video is available here: https://youtu.be/-Mqe7MNBpcA