The MK1 came with a Sunroof as standard, Aircon was a cost option, if you had AirCon you still got the sunroof.
Other options were:
Leather
Passenger Airbag
Metallic Paint
CD Boot Changer
And that's all I think.
The seats are heated, both the leather and cloth versions (same as HLX I believe)
When the MK2 first came out, they came with a sunroof and the Aircon was a no cost option, but, if you got the Aircon you didn't get the Sunroof. The later 155's came with Aircon as standard (dunno when this changed) and teh sunroof was a cost option, I'm not sure you could have either / or on the later 155's.
Leather again was an option on the 155's as was the Passenger airbag, metallic paint and Boot Changer.
I beleive (correct me if I'm wrong) the Passenger airbag became standard on the later 155's.
The MK2 also came with color coded headlamp washers, the MK1's were plack plastic.
The MK2 has a HGT badge on the boot, and 155 badges on the wings by the side repeaters, the MK1 only has the HGT badge.
The Radios in the MK1 had push buttons for volume up and down, the MK2 has a rotary dial.
The Aircon on the MK1 was a standard non climate control type, the MK2's is a climate control type of AirCon.
The MK2's came with a digital odometer, the MK1's is analogue.
The wheel size is the same but the alloys are a different design.
Um, I can't think of owt else, Anyone else?