I'm borrowing the work I did on another 85 442 SPID I did last week I think. Saves some time.

Here's how your SPID breaks down.
ARL- Arlington build plant code
AR9- Reclining buckets, (standard on Salon)
AU3- Door locks, power
A01- Windows, tinted
A31- Windows, power side
BD2- Cutlass Salon ornamentation- Delete (Included w/W42) *Note* This deleted the trunk lock and edge trim, door rockets, and sail panel "Cutlass Salon" emblems.
BS1- Sound deadener, Extra. *Note* There is a "deluxe" sound deadener package of BS2 for extra quiet.

B34- Floor mats, carpet, front
B85- Moldings, wide belt reveal, bright (outside, on top of doors)
B93- Moldings, door edge guard
B99- Wheel Well Molding- Delete (Included w/W42)
CD4- Delay wipers
C60- Air Conditioning (required w/W42)
C78- Roof interior dome light, w/single reading lamp
D34- Mirror, Visor Vanity, Passenger
D35- Mirrors, dual sport, remote driver, manual passenger
D55- Console (standard on Salon)
D7I- Gear, speedo driven
D85- Stripe, special accent (Included w/W42) [not sure how this correlates with Y64, but it may be referring to the bumper stripes]
E5Z- Less speedo gear adapter
E7Z- Less speedo sleeve
F41 - Sport Suspension Pkg. (Included w/W42)
GMD- Stumped. I've seen these on GNs as well. It MAY be the rear end 8.5" housing? I don't know. Have yet to find a definitive answer on this.
GT4- 3.73 rear differential
G87- 8.5" ring gear
JM5- Disc/drum power brakes, dual diaphragm booster
K64- Generator, 78 Amp, included w/C60
LG8- 307cu. in. Hi Output V8 Engine, (Included w/W42)
MW9- TH200-4R (Included w/W42)
MX0- Marketing code for MW9
NA5- Emission system, Federal (non-California)
NP5- Sport steering wheel, leather wrapped (standard on Salon)
N10- Exhaust, Dual outlet (Included w/W42)
N33- Tilt steering wheel
N83- Wheels, Chrome 15x7 (Included w/W42)
QYH- 215/65R15 ROWL tires (Included w/W42)
TR9- Lamp Group, Convenience
TT5- Tungsten Halogen Headlamps, *Note* These were hi-beams only. (standard on Salon)
T83- Black inlay headlamp doors (Standard on Salon)
T88- Parking lamps front, amber (Standard on Salon)
UM6- AM/FM Stereo with Cassette
UQ1- Radio Provisions for Stereo
UT1- Tone generator, warning (Standard on Salon)
U21- Gages, instrument panel, (Standard on Salon). U.S. cars got an 85 MPH speedometer.
U25- Lamp, Trunk
U26- Lamp, Underhood
U27- Glovebox lamp
U29- Footwell underdash courtesy lamps
U66- Speakers, extended range
U75- Antenna, Power
VD6- Bumper Support Front, Aluminum
VD7- Bumper Support Rear, Aluminum
Not Listed, but still should have been included- VK3- Bracket, front license plate (standard w/W42) *Note* This code was not always listed but every VIN 9 car should have came with one.
VT5- Color Keyed Bumpers (Included w/W42)
V08- Cooling, Heavy Duty
V1P- Stumped. It is NOT "VIP". It's POSSIBLE it may have something to do with the body break paint lines being different than normal, but again, no verification on this.
V30- Bumper guards, F/R
V73- Statement of Vehicle Certification- U.S.
WL7- Popular Option Package Discount code *Note* Dealers HAD to put this RPO in if customer ordered the qualifying stuff, otherwise no discount.
W42- 442 package (Available on Salon only)
YT1- Deluxe Door Panel trim 442
YT9- Option package, Fisher supplied parts
Y64- 442 package ornamentation- Decals (Included w/W42)
Y78- Cutlass Salon- Changed VIN from GR47 to GK47.
11U- Upper body color- White
12L- Lower body color- Metallic Silver
6NY- LH front spring code
7YK- RH front spring code
79I- Claret interior trim
79R- Claret vinyl interior seating and upper side panels
799- Claret Seat belt webbing
8PZ- LH rear spring code
9PZ- RH rear spring code