I did some research and found that even the fan fret tremolos would be too short to fix the Jazzmaster.
For this reason I think I will put in a telecaster bridge (Wilkinson WTB) as it will cover the pole holes and routing and allow an ashtray cover. Let's be honest a monstrous jazzmaster/jaguar with four pickups and a tele bridge will probably look pretty rad ... but probably could use something to tone it down.
I will reroute the tremolo routing so it takes a tele single coil and add another Warman dual blade pickup (T-Raill Blazer). As the guitar has an awful lot of switching options anyway I will stick to that path. I haven't quite settled on which options to add because I am not sure whether it is more useful to do some parallel/serial/single coil stuff with the lower pickups or rethink the whole switching concept.
A quick and dirty idea of what it could look like without the cover.
Nothing new on the Tele as soon as I have enough time to spend a weekend in the workshop I will drill string through holes that are further back into the babicz and see if it is still restringable or breaks the string due to the back and forth angle going on. If the later should be the case I would switch to a hardtail bridge and a pickup mounting frame.