Knocking sound in front right wheel area when brakes are applied at low speeds

Recently I had my wife's 2004 Nissan Altima V6
Automatic tran get some repairs done. The
suspension was horrible and so were the brakes.
We ended up replacing the suspension/struts,
calipers(new ceramic),CV joint(front right) where
noise is coming from and bought all 4 new rotars
too but I was told the after market ones on it were
just fine and actually better than the new ones i
bought(they had grooves and holes in them).
We called auto zone about getting this cv joint
needed and scooped it up that day since all other
work was being done also.  The guy at store gave
me a CV joint for ABS after i clearly told him it was
not ABS on front.  Did not realize until back at
buddies shop. So, when I called him I was told to
take a hammer and just knock off that 44 ABS
TEETH piece and it would be the exact same....
Well that was not easy at all and after beating at it
with hammer and chisel like tool for 20 min my
buddy said it's same exact size and teeth "might "
not matter because it's same width as spacer on
old one;which it was. We got everything finished
and been great for last  3+months until today a
knocking sound started coming from that front left
area as I was braking in her car. The knocking only
happens when getting to lower speeds(45mph
&down) Slower the car gets ,the Slower the
knocking gets also. Oh, on the way home i started
trying to slowly apply ebrake which worked without
noises. i also tried applying brakes very lightly until
it came to stop and both kept it from making
knocking sound which seems to be getting louder
and louder almost...
We have 2 little kids and one on the way so I want
the car working as best it can obviously.
ANY HELP IS VERY APPRECIATED and thank you
prior for any help or ideas before spending more
money i can't afford...