Interesting...
I can't read the part number of the ECM, but it looks like the last number is a 7. The others... ?
Looking at Tunercat, I came up with a bunch of ECMs that end in "7". But only one that appears like it could be a match. 16183247. Actually sort of looks like the part number on the label.
With that as the best guess, I came up with the following...
16183247
95 Buick / Pontiac L36, 3800, V6
16183247
94 - 95 Buick / Pontiac L27, 3800, V6
16183247 or 16197428
94 - 95 Buick / Pontiac L67, 3800, Supercharged
All of these would seem to indicate that the car houses a 3800, series 1, of some sort. Possibly supercharged.
Here's a "flipped" pic of the ECM. See if it looks like what I said, or see if you can come up with an alternative.
(You can most likely do a "save as" and then reopen it in Windows Photo Viewer. it will allow you to expand it.)