There are 3 different codes for the HD trannies, not the HD and non-hd trannies. (although there are different codes for those as well) This is not the same as the package number that is on the sticker in your trunk or wherever, this is a number that is on your actual transaxle somewhere. This was the case in my STE, even with my vin number (which gives them all of the codes on their computer that are listed in my trunk), the dealer told me I had to look at a number on the tranny because there were 3 different versions of that particular transmission used that year. They couldn't however, give me a straight answer on whether you can interchange them. I am pretty sure you can't swap all the parts out (although you MIGHT be able to), but I dont know if you can just swap the whole thing or not. My suggestion is call the dealer and tell them your situation and see if you can swap them out or not, otherwise I can ask at the dealer the next time I'm in there for you, but I would imagine they would be interchangeable, I don't see why not... What could be different about them? They aren't going to change the wiring harness (if they did that would be really stupid and pretty costly), and it obviously is going to bolt to the block the same, so I can't really see why it woudln't be interchangeable.
1990 Maroon Grand Prix STE McLaren 3.1 Intercooled Turbo, 14.695 @ 94.49 on 12psi before cam/heads/etc.
1990 Bright Red Grand Prix McLaren 3.1 Intercooled Turbo, 14.819 @ 92.72, 189whp
1999 Grand Prix GT 9.75:1|K&N|160 tstat|No Ubend/Cat/Res|UD Pulleys|Ported M90/TB/Heads|XPZ|2.55"|Pacesetters|Stage 2 I/C. 12.442 @ 112.78
2000 Blue Bonneville SSEi Supercharged Gutted Airbox|K&N|3.4"|1.9'*|WP Pulley|Custom DHP|180*stat|41932'*|No Cat. 14.681 @ 94.80
2002 Dark Cherry Grand Prix GTP Supercharged & Intercooled
12.084 @ 114.38 w/1.743 60', 315.6whp, Fastest Stock Cam M90 GTP!
NOW XP CAMMED, 340.6whp with XP, stock heads, Gen 3 M90, 11.984 @ 115.84 w/1.750 60'!
Most HP Stock Heads Gen 3 M90 GTP!
2004 Red Monte SS Supercharged K&N|3.4 Pulley|1.9'*|180*stat|41919 plugs|3" dp|No cat/ubend|DHP|Shift Kit. 14.2 @ 98
GOT BOOST??? Friends dont let friends drive stock!