Not solved for bonnet release mod yet but have a batter charging via tender mod using magnetic charger adaptor and some cables. Hardest part was working out the magnetic connector polarity hence the spare fuses 🙂
Use pigtails from batter tender to connect to car battery, use extension cables to connect pigtails to magnetic connector using space connectors, use other extension cable to hardwire to other part of magnetic connector which in turn connects to the cable from the battery tender.
Thule fixing kit 5178 does the job. Paired with Thule footpack 7105 and Evo 135 bars. I think you can use other Thule footpacks and there are certainly other Thule roofbars. Trick is to follow the spacings as per the instructions precisely, fully loosen off the foxings when attached to the footpacks (use supplied allen key to loosen off as much as you can after slotting the fixing into the footpack) before placing, per spacing specs, onto roof. When on roof, make sure footpaks are properly seated into roof channel and then start to tighten one side, only do about 3 turns before doing the same on other side. Alternate between sides using the 3 turn method until each sides are torqued. This method prevents the footpack on one side popping out of the roof channel before the other side has been fully torqued. It helps to have tow people.
2019 Outback - Full-size spare fitted straight into my wheel well. Original kit was a pot of slime and a pump. (Not even a micky-mouse skinny wheel). To my mind, not good enough for a car with off-road capability, so I bought a spare. Had to go to the dealer to get one that matched the already-fitted 18" alloys. Cost about £400 with a cheap tyre! It included the foam plastic insert for the jack etc. This insert is apparently for the 17" wheel. As mine has 18" alloys it rattles about a bit. It was also a bit tall, so I modified it with woodsaw - fits much better now.
Only thing to watch for - if you have big knobbly all-terrain tyres, they may not fit. Have to measure the OD. My wheel well is just over 28" diameter, leaving about 1/4" or so.