'86 and '87 Buick 3.8 engines (and '89 TTA) all used the same aluminum casting for the throttle body. But there were different part #'s depending which pressed in fittings were used for throttle body cooling.
'86 - '87 turbo Regals have throttle body as you show. that sticker has the GM part # for the TD-7 designated throttle body. The pressed inserts for throttle body cooling are as such - one under, behind IAC housing is angled while the other one on opposite side from photo is straight.
'86 - '87 other car lines using the 3.8 naturally aspirated, fuel injected engine had the throttle body rotated sideway from vertical. a metal bracket installed via those two screw holes shown in pic (as well as a 3rd screw hole above the linkage arm) to cover the linkage assembly. See attached pics. with the rotated throttle body, the coolant insert fitting on the side of the throttle body is a 90* fitting vs straight on the turbo regals. This throttle body has a different GM part # than the turbo regals and the sticker would show TD-6 designation.