Does anyone know off-hand if there's a strut that will accept '04 sti springs, and also hook up to a '99 legacy suspension set-up?

You may need to mix & match top hats to get everything to fit. Check out these threads on the Legacycentral bbs regarding fitment. The 99 Legacy pretty much has the same suspension setup as the 92-94 Legacies.

 

http://bbs.legacycentral.org/viewtopic.php?t=22419

http://bbs.legacycentral.org/viewtopic.php?t=2153

Did any '99 Legacies get the rear multilink suspension?

You can use stock '99 struts for the '04 springs. Or '02 to '05 WRX struts would also work and there's probably many more options for those.

 

I have '02 WRX KYB's on my '91 SS - using '06 STi springs - ride height didn't change appreciably. They have the same cone-shaped rear springs that match my stock strut tops. But '04 would be conical and would match your '99.

 

GD

Edited August 1, 201213 yr by GeneralDisorder

Did any '99 Legacies get the rear multilink suspension?

 

No, I believe they didn't get the multilink rear end until 2000.