i would ...
put a JB in the bridge, texas special in the neck.
leave the pickgaurd alone.
add a slider switch to split the JB for single coil.
(maybe jag-plate it with the 3-way)
lightly steel wool the back of the neck & see if that feels fine
graphite string trees (because the roller trees are worthless)
schaller tuning machines
schaller straplocks
(if the money is available,) tone pros bridge/trem
to "hardtail" it, just cut a block of wood to fit in the back cavity between the trem block and the "butt" of the guitar (opposite side from the springs).