Well I have done some research for the shocks I am having put on this week. I had to take it to a garage because I couldn't get the bolts off. And the garage had to cut them off anyways. Stock shocks in Pennsylvania winters for the past 14 years.
Pro Comp shocks on my 97 Expy with TT and 3" spacers in the rear. I bought them from 4wheelparts.com with free shipping they were 39.99 each.
Part number: EXP917517 with measurements of 17.08 in. extended; 10.58 in. collapsed.
Part Number: EXP924504 with measurements of 24.84 in. extended; 14.82 in. collapsed.
Without a the leveling/lift kit (Stock) the Pro Comps have a different part number
Part Number: EXP915511 with measurements of 15.69 in. extended; 10.02 in. collapsed.
Part Number: EXP922504 with measurements of 22.58 in. extended; 13.71 in. collapsed.
It's my understanding (and there are a lot of members on here) running the stock shock height and can vouch when I say they work just fine. However they do make some longer, I believe for more wheel travel?
Here is a link for Rancho's RS5000 series shocks for the 1"-2.5" leveling/lift too.
http://gorancho.com/shock_lookup.php?cat=shock&year=1997&make=FORD&model=Expedition+&drive=4WD&height=1.00-in.+-+2.50-in.&submodel=All+Models&x=47&y=8
Hope this helps.