FWIW the slug coil of the Custom, regardless of magnet, sounds very Strat like and almost has quack on it's own (the coil by itself sounds like Lay Down Sally or Sultans of Swing a bit). But also, a Custom Custom or Custom 5 in parallel sounds very Tele like. In my Jackson, I have a Custom Custom in the bridge and vol/tone push pulls wired like a triple shot, so full humbucker I get a Custom Custom (hot PAF A2, which is EVH/DiMartini territory), vol up I get slug coil (Strat sound), tone up screw coil (sounds like a cheap punk P-90) and both up parallel coils (tele sound).
If you're going to have to route for a Tele pickup, there might be other ways to get there, like the Duncan Twangbanger just drops in to a Strat pickup route, or a Custom, if it's already routed for a humbucker under the pickguard.