Guess I'll toss in my 2¢ (not my $0.02).
My 95 Grand had this problem. I replaced the front springs with Moog Car-Go coils, replaced all four swaybar bushings with polyurethane Moog units, replaced the tie rod ends, the front struts, and the strut bushings. The clunk was still there.
I finally gave the van away. The new owner brought it in to a shop for an unrelated issue, and they discovered the front swaybar was cracked. $25 for a boneyard swaybar later, the problem was solved.
FWIW, Carl