well ive swapped a 5.0 into a 65 mustang and i can tell you that everything fits well sort off, remember its a ford so it doesnt realy without a little thinking.
the heads have oval exhaust ports, so it is imperativ ethat you get the SVO street rod headders, as hedmann and others for sb fort are for the old style. there is no clutch boss, or fuelpump boss in the 5,0 block.. but if you retain the fuelinjection youll be fine, otherwise electric fuelpump.
With regards to pulleys and brackets, look no further, just get a set of march pulleys with mounting for alternator and tensioner. looks awsome and relatively cheap. plus you retain the poly v belt, that you never throw or squeak.
i have a ford motorsport manual that describes the mounting of the wireing harness in a non.efi car. e-mail me at firstname.lastname@example.org if you are interested in a copy