old guy needs fun modern-ish driver

Ill just leave you with my thoughts. Mustang is a good choice Fox or SN95. I have an 86 Fox convertible and it is fun, but I wouldn't mind an SN95 coupe for example.
the reason is, Convertibles are heavy not really a platform for go fast etc. If you are only seeking V8 street cruising Mustang convertibles are around fairly affordable also. convertibles are also considerably higher maintenance and it is said a top needs replaced every 5-7 years. definitely something that needs to be garage kept.

Another alternative is the Dodge charger sedans of the 2000s. I see them around and they seem zippy on the highway. I also remember a Dodge station wagon type thing of the same era. i think they called it magnum, and that if i recall correctly was AWD I don't know if they made a RWD version.

Of course there is the Chevy Camaro/Firebird up until 2002. and the Chevy Impala SS or any V8 caprice type RWD, as well as the El Caminos and Monte Carlo SS and the 80s Malibus etc. if you can find them in good shape.

Other Ford V8s. the Crown Vic, Merc marquis, and the Lincoln mark series and Town car.- still made 20 years or so ago not too old yet..but getting there. probably real cheap noone wants em, but good big car riding cars...

lets not forget all the GM big cars , Pontiac, Olds, Buick and Cadillac if you can find 'em.

After that, 2WD Pickups is all I can think of. man V-8s are being phased out it seems...:)

Old Police cars maybe...?