I've got a Scroth Rallye3 harness in my SVT. Here is how I installed mine:
- I used the rear-most mounts of the front
seat rails to mount the lapbelts. Simply
take out the bolts from the rear seat
rails (10mm I believe), slip the Scroth
eyelets under the rail (you'll have to
bend the eyelets about 45 degrees), and
reinsert the seat rail bolts. You might
want to add a washer to the other rear
bolts (there are 2 on the end of each
rail) to keep from bending the rail.
- The rear mount used the rear lapbelt
mount. Pull up on the front of the rear
seat cushion (a quick jerking motion works
best) and the seat pops out. You'll
need a torx wrench (#55 I think) to remove
the seat belt mounting bolt. Add the
Scroth eyelet and bolt it back down and
put the seat back.
- I also have a custom anti-submerine strap
('crotch strap') to keep the lap belt
from creeping up when the shoulder belts
are tightened.
- You MUST NOT mount the rear points more
than 45 degrees off horizontal. If you
try to mount the rear points to the
front seat back, you will be crushed
during an accident.
- As for rear passengers, that's why I got
the Rallye3. It's got a quick release
so the back seat can still be used.
I only wear the Scroth during racing, but
keep it installed at all times. The
belt is tucked in the map pocket of my
seat (it's still mounted), and can be
pulled out and buckled in about 1-2
minutes.
You'll have 2 rear mounting points (unlike my 1 for the Rallye3), but the same logic should still apply.
Good luck