I have a 97 explorer shortblock in my car right now. I'm very happy with it. I checked the crank, the thrust and main bearings, bore taper, and general condition before I bolted my Performer heads and intake on. After close to 100K, there was virtually no wear and the cylinders still hone marks and no ridge! After a few mods (tapping and plugging the dipstick hole at the base of the block, I put my vintage parts back on. With Ford Corporate blue paint and ported K manifolds and stock valve covers (with 1.7 roller rockers, so I needed two ROL thick valve cover gaskets) it looks quite stock.

With an HO cam from a 1990 Mustang, it performs quite well up to about 5500RPM with a strong low end. :biggrin:
Notes: The GT40P heads are a mid-97 issue, so if it's a 97, it could have the GT40 heads. They aren't bad heads themselves...

If you go to fuel injection, use the existing intakes--it's very similar to the GT40 intakes used in the 93 Cobra and has a larger-than-5.0L Mustang 65mm throttle body.
Swapping to a vintage block you may need a 50oz balancer, a clutch pivot adaptor for MT (I used a cable clutch), vintage timing cover, distributor and hardened steel gear and a few other items depending on your application.
I only needed the shortblock, so I sold the heads and the intake.
Daniel