3 quick problems

Am I better off to just drill this out and replace the whole guts? Seems like even after getting through the back seat this is kind of a pain in the *** so to speak. I'm not opposed to drilling it if that would be easier, since I have no real attachment to the lock cylinder that's in the car

Come ON. I'm 69 and have lots of arthritic-like issues. It is not all that much work to remove the seat. Throw together some extensions and a 1/2" socket and tape them all together. Put down a mat, cardboard, "whatever." Lay down, stretch out, and reach back with the "tool" and unscrew the bolts.

This is as opposed to "drilling out the lock" which has a HIGH likelyhood of breaking a bit/ slipping off with the drill/ and then.......dicking up the trunk lid.