Well, I had a first go-round this evening. I took the Warwick and, armed with the Warwick videos posted here, I went step by step. Things seemed ok. According to the way they wanted me to measure stuff, I didn't really adjust the truss rod that much. Maybe not even half a turn. Then the nut adjustment. Again, thankful that this one is mechanical.
The bridge is where I really started to get confused. First you have to "release" the bridge. Then you can move the whole thing up and down. Then you begin by setting the string height on the end strings so they rest on the bridge. Meanwhile the magnets of the pickups (also poorly adjusted it seems) were pulling all the detuned strings down onto the bridge anyway, so I lowered them just to get them to stop doing that. I think I got the G and B strings in the right low position, just resting on the fretboard. Then you're supposed to adjust all the middle strings according to the radius of your fretboard...so eyeballing it.... When I think I've done that, it's time to raise the whole bridge again such that the strings are 2.5 mm above the highest fret... Then lock everything down again, each saddle and the whole bridge. Then it's on to pickup height. Fret the strings on the highest fret and put the pickup 2mm below the string. Or something.
Anyway, the end result is...a noticeable improvement? I had hoped for more, given that this bass has played like crap since I acquired it two plus years ago. I think I'll be having another go-round tomorrow. I have to lower the action more than this.