Have you guys gotten a weight waiver from HQ for that thing?
Good call. A Land Rover Discovery Series I is over the 4200 pound limit.
Please note, thebeedubya, that the rules refer to the "vehicle’s original, manufacturer-stated curb weight" so it doesn't matter that you're probably planning to make it lighter by removing a bunch of stuff. If the original weight is over 4200 pounds, you need a waiver and it is very much worth asking before spending any time or money on the project. As I have learned from personal experience, HQ sometimes does say no on weight waivers even if it's only for a couple hundred original pounds that would have been removed during the build anyway.
1982 MG Metro 1300: IOE 2015 Pacific Northworst GP, Longest Distance 2010 Cd'L Box Wine Country Classic
1980 KV Mini 1: Worst of Show and Fright Pig Supremo 2009 Concours d'Lemons
1978 H Special: Second-Round Elimination 2010 Lemons Pinewood Derby at Sears Pointless
1967 SAAB 96: IOE 2012 Pacific Northworst GP