Grey,
As-long-as-your-rear-springs-are-in-good-shape,-(not-broken-or-severely-rusted-at-the-bottom-isolator)...-then-the-Bilstein-"B4"-shocks-are-a-direct-replacement.
However,,,-I-think-you-may-be-getting-some-different-front-shock/spring-fitment-issues-confused.
1----If-you-do-the-Jag-Bilstein-shocks-on-the-front,,,-then-you-would-want-to-do-them-on-the-front-also.--BUT...this-leads-to-replacing-the-front-factory-LS-springs-with-Jag-"S-Type"-springs.--Reason-is-the-bottom-spring-mount-on-the-Jag-Bilstein-shock...is-larger-in-diameter-than-the-bottom-of-the-factory-LS-spring,-(as-BCA-has-pointed-out).
2----The-reason-for-using-2002-or-earlier-Jag-"S-Type"-shocks-on-the-front-of-the-LS....is-because-the-2003-and-later-"S-Type"-shocks....use-a-different-lower-mounting-system,,,-that-will-NOT-work-on-either-GEN-of-LS.
Last-time-I-checked...the-LS-factory-shocks-were-NLA---That's-the-reason-for-the-Jag-conversion-parts.--However.....
3----Even-though-the-rear-LS-springs-will-work-with-the-Jag-Bilsteins,,,-the-LS-suspension-will-be-"unbalanced"-since-the-front-Jag-Bilsteins-won't-work-with-the-front-LS-springs,-(as-mentioned-in-point-#1)
Having-done-the-rear-suspension-rebuild-on-my-LS-a-few-months-ago...using-all-jag-parts,,,-I-can-say-for-a-fact-that-it-made-the-LS-"front-heavy"-through-turns...and-very-harsh-over-bumps.
Having-just-done-the-front-suspension-rebuild...preliminary-results-show-a-better-balance-and-handling...and-as-with-the-front,,,a-slightly-stiffer-suspension.
I-have-many-pics-documented-of-the-front-rebuild...and-will-download-when-I-have-time.--Work-is-still-taking-up-much-of--my-time...so-stand-by.