Hey guys, just a quick update here.
Had a get together with a friend who also has a jazz bass and he allowed me to temporarily borrow his pickups and control plate to do a bit of troubleshooting. Trying his control plate with my pickups darkened it up ever so slightly so it might partially be the 250k/500k issue, I also used his quarter pounder set with both control setups, and in the end my bass with the electronics of his sounded pretty monstrous.
So now I'm going to purchase myself some 250k pots, a set of SD QP's, and I'm probably going to add a series/parallel switch into the mix also (I figure I'm redoing the thing anyway I might as well have a few more options). Somebody mentioned getting a "loom" from kiogon, Is he a member here? and, if so, How would I get in touch with him?
Pretty much did everything you've mentioned above with an American standard Jazz I had, other than fitting SD's I fitted model J di marzios. Everything was still to bright. Flatwounds are a cheap option. Just put kiogans name in the search toolbar and send him a PM