OK, Finally got this to work....Only got a momentary glimpse of the inside....BUT, the Cop Cars HAVE NO ENGINES !!! Now, that's cool, or what ? Allright, here's what I done....
Got the Cop Car to crash at the far North set of steps, turn upside-down, waited for trouble meter to run down, got on the bike, attempted to jump it on top of the car....Took many tries, as the Car was always moving around.....Got the bike on top, dismounted, and was thrown off by the movement of the car......
Next time, gained the top, but the Cop jumped on the upside-down car with me, so I got off real quick and kept trying....In the meantime the car just kept moving, winding up at the South set of steps....As I kept trying to jump on, the car moved up against the stone wall that runs in front of Shinjo's, and I could then jump on the wall, and then jump on the bottom of the Cop Car....
Could still see the empty engine compartment, but was solid floor pan on the car...Until I would shift to aim mode (up Arrow)...Then Jimmy would just slowly sink INTO the car, and eventually it would "spit" him out....I kept doing this over and over with just that one look inside.....
Total time on clock was about 9 hours I spent doing this, until passed out.