So your looking for a BBP spare tire ??
So your looking for a BBP spare tire, and you got some conciderations like its got to clear cordoba big brakes, maybe rear discs too. It has to load flat in the spare tire well, and have a large enough outer diameter because of the limited slip you may have etc. A lot of conciderations to be sure. I have your answer. Look no further than last gen RWD lincoln town car, grand marquis, crown vick up to 2003. Dimensions are as follows
Width 5.5"
Outside diameter 25"
Inside diameter 14"
5 bolt 4.5" circle
Aluminum or steel construction.
16" rim and tire
I picked up 2 of these at a high turn salvage yard in Dallas last week for $10 each, and they had never been driven on. Because these cars for the most part lived a pampered life, the wheels and tires were brand new. I wish i could have found both of them in aluminum, but took what i could get. A little simple green and a garden hose, and they will be just like new. Take your tape measure as theres other ford donuts that look close enough to fit, but the inner diameter wont clear.
Hope this helps
Matt