Wheels!! or brakes/suspension?

[19seventeeCustom]

hey guys,

I'm getting ready to change the wheels up on the '70 and was going to go with a set of 20's and lower the truck another 2/3 all around.

Anyways, the problem im having is that the previous owner put disc brakes on the front,, well no problem right? They used disc brakes and spindles from a seventies mid size car so I have 5x4.75 bolt pattern in the front, and I assume drilled axles for 5x4.75 in the rear. SOOOOOO,, do I go ahead an purchase wheels with that bolt pattern? instead of converting over to 5x5?

Will it change the backspacing needed on the front? Im sure there is a much larger selection of 5x4.75 wheels than the 5x5 but i dont want to order wheels and find out they wont work with my setup????

thanks in advance guys