Common to have issues with the 87-93 Saleen front calipers, as they had large 73mm plastic pistons, which tend to seize up.
The good news is that for a few $$$ extra, you can specify metal pistons from most brake companies, even the parts store rebuilders.
I like using Rockauto.com - lots of choices and great prices. Just look up a 1989 Lincoln Mark VII.
MOST 87-93 Saleens used the same brakes... However Saleen was known to substitute based on what was available, so always best to check what you have before ordering up a bunch of parts. Plus, sometimes previous owners do some crazy/misinformed things (like my 91 had had a 60mm caliper on one side and a 73mm on the other).
The 87-93 Saleen front brakes are mostly SVO/Lincoln Mark VII pieces - 73mm front caliper with 11" 5-lug rotors.
Some of the common Part Numbers are:
Left Caliper -
CARDONE Part # 184151
CARDONE Part # 184151S (with steel piston)
CENTRIC Part # 14161024
RAYBESTOS Part # FRC5242
AUTOSPECIALTY / KELSEY-HAYES Part # 4181024
CENTRIC Part # 14261024 (Posi-Quiet Loaded with pads)
AUTOSPECIALTY / KELSEY-HAYES Part # 4081024 (Loaded with pads)
Right Caliper-
CARDONE Part # 184150
CARDONE Part # 184150S (with steel piston)
CENTRIC Part # 14161023
RAYBESTOS Part # FRC5241
AUTOSPECIALTY / KELSEY-HAYES Part # 4181023
CENTRIC Part # 14261023 (Posi-Quiet Loaded with pads)
AUTOSPECIALTY / KELSEY-HAYES Part # 4081023 (Loaded with pads)
87-most 91 Saleen rear brakes are also SVO/Mark VII pieces with a 54mm caliper and 11.25" 5-lug rotors.
Ford changed the Mark VII brakes in 1991, so some 91-93 Saleen rear brakes were 10.5" rotors with a 45mm caliper.
Always best to check the rotor diameter before ordering parts.
You are correct that Saleen used the SVO aluminum master cylinder for most cars. Although there are exceptions, including using a 1" aluminum master cylinder from a FRPP / Crown Vic application...