I did this route in 2017.
Gilgit to phandar, phandar to shandur & shandur to boni and then central chitral, kailash Valley.. Lowari to Islamabad.
I had a Suzuki liana 1.8 automatic, and we are very old experts in hilly areas... Phandar to shandur is doable...
Shandur to laspur the first village of chitral is also doable...
But laspur to boni is a nightmare.. You'll have to pass from large Rocky stony path for hours on 0-5kph with all passengers shaking and cursing you...
And if godforbid you burn the clutch or get the chamber hit, you're done...
I won't advise you to take your car to this route.
And one more thing after doing this route once you'll reach chitral you'll loose interest in chitral Valley and you'll regret ur decision.. So my opinion is do babusar top to hunza khunjerab and phandar to shandur and go back via babusar top...
Visit chitral from other side isb to chakdarah motorway is on so chakdarah to chitral is nearly 4-5 hours.
So on that trip you can plan kumrat /Dir /kailash/boni meadows /hot springs
It will be a long 6-7 days trip itself too.but don't mix your plan with this plan...