Fuse Size for Fuse Tap for Dash Camera

Yes, low profile mini ATM like this:

 

Same, I got this

not sure if it stripped the link, but you can search this on amazon
"E Support 12v Car Add-a-circuit Fuse TAP Adapter Mini ATM APM Blade Fuse Holder Pack of 5"

I snipped the ends off and chose to solder it myself.

I think you are in that other thread, but here was the pics and grounding I used are in this post

Hard wiring a dash cam | Page 2 | PriusChat

 

The original small fuses are Pacific Engineering Corporation’s BFLP series; see the catalog page, customer drawing, and specifications (in Japanese). These fuses are marked with Yazaki’s ’543 patent, but the blades are slightly wider (10.9 mm) than other low-profile mini blade fuses (10.0 mm), including Yazaki’s own products. I don’t know if the difference in width is practically important.

When I needed a few hundred milliamperes of unswitched (hot battery) power for an accessory, instead of a fuse tap, I installed a pigtail repair wire (Toyota part number 82998-24290) with a pre-attached 0.64 II [F] terminal in connector 3F, position 9, and added a 5 A fuse (90982-09019) in the corresponding vacant position on the Instrument Panel Junction Block Assembly. I then spliced the accessory’s wire, which had its own in-line fuse of a rating suitable for the accessory and its wiring, to the repair wire. The results are less obtrusive than a fuse tap, and I believe they will also be more reliable.

There were some trade-offs, of course. If the new terminal must ever be removed, I would have to use a terminal removal tool to extract it. I was also careful when handling connector 3F, since the housing is not available as a Toyota service part; if I had damaged it, I might have had to buy a full wiring harness, new or from a junkyard, to get a replacement.

They are for the European version, but these diagrams of the IJB connectors and inner circuits and an old version of the Wire Harness Repair Manual may be of interest. I consider a review of the complete, vehicle-specific Electrical Wiring Diagram (available by subscription to techinfo.toyota.com or toyota-tech.eu) essential when planning modifications, though.

Note: I don’t know the details of your added load, nor your skills as a technician, so consider the above as general information, not an engineering design. I recommend against modifying your Prius at all, except perhaps by installing Genuine Toyota Accessories.

 

I've installed mini ATM (not low profile) fuses into the fuse slots with no problem as well.