ok, i just had the second part work in a very strange way... i wanted to glitch in a 9F off the street, did the whole shebang, and actually ended up driving out of my garage in the 9F (first time i got this far after i before lost 3 supers and, this one pissed me off, a Monroe i took of the angry driver dude).
this is where it got strange; right after the animation of driving out of the garage ends, my char gets out of the car, and the car doesn't show as PV on the map. i thought i'd just try backing it in anyway, that's when i got the "garage is full, replace a vehicle?"-prompt as with non-premiums. ok, i hit accept, and got the list of cars while standing in the garage, looking at an empty spot where the rebel was. and instead of the rebel the list you get when the garage is full shows the 9F, but as "destroyed". i wondered if i should just back out and try calling mors mutual, but decided it'd probably be less risky to just exchange it. did that, but the spot stayed empty. so i walked out of the garage and called mors mutual anyway, guessed it couldn't hurt trying. and there, lo and behold, was my 9F, ready to be claimed for around 1600 bucks. did that, got the car, glitch worked. just different than expected.
anyone got an idea why this happened? i heard of glitches involving mors, so yeah... anyway, glad i got an almost free 9F.
Edit: just drove the 9F out of the garage and got blocked by something invisible. the car backed up a little, then the door opening animation started again, and i drove out next to a pretty beaten looking 9F. i didn't check if it was still driveable, maybe even a sell-able dupe, because an armored truck drove by and i went for it. as the 9F isn't the actual car i wanted to glitch in, more of a test, i then went to sell it. but it would only get me 1800 bucks at LSC, which is pretty sh*tty considered i paid almost as much foor the insurance claim. this is getting weirder and weirder...