Dude you need to cool it with all these wheel posts. You can ask these questions in the same thread.
They 10-holes are 15x7, the Ponies are 16x7, as I just told you on Car Domain. I'm not sure of the offset, I'm sure someone else here knows.
No, all 10-holes were 15" (and they came standard on 5.0 LX's from '87-93). Turbines came on GT's from '87-90. '91-93, Pony wheels were optional on LX's and standard on GT's.
2.3's came standard with 14" steel wheels with hubcaps, or 14" "polycasts" were optional, and then 10-holes were optional above that but I don't know if they were available from '87-93 or what.