Why wont my car start? (Electrical issues? Need wisdom-Ford Focus 2000 standard motor-)

My car doesnt start at all and has not
for weeks.
One day my battery light came on
,and the next day im driving it down
the interstate and cluster in the dash
went out, my lights began to dim(it
was 2 am) as i was getting off the
next exit to investigate it kept kicking
off but would kick back on (probably
only because it is a standard , and if
the wheels are moving the engine
WILL kick back on.. ) had it been an
automatic it probably would have died
altogether. But it kept kicking on, my
gauges are going crazy spedometer
going 0 to 140 to 0 to 140 and all the
gauges doin it together. When i got to
the exit it died as soon as i slowed.
We pushed it to the gas station. While
waiting on help we tried push starting
it but it just kept dying. Tried jumping
it it did the same thing . ended up
replacing the battery (which wasnt
bad) the next day i dropped a new
alternator in it (i shouldve tested it
first bc that wasnt it either..) And now
ive replaced the cranksaft ventilation
hose but i think thats unrelated  the
prongs just broke off . im so fed up,
the gauges still jump , the battery is
losing power quickly but even
charged all the way up it cranks but
wont start. I have considered my
timing being not right or the fuel
pump but the symptoms just dont
sound right.. Im starting to think it will
just be an endless search for a bad
wire. Please help!

Tonight i am checking connectors
and any grounds i can find.