Big brake kit 69 Chevelle

I have a 69 chevelle with drum brakes, & would like to upgrade to your big brake kit front & rear. I have 20x8.5 with 5.5 bs on the front & 20x10 with 6.25 bs on rear. I need to know if your kits will fit with that wheel setup & if I was to run your dropped spindle would that effect the backspacing compared to the drums. Also i want the power disc setup could you give me the correct part #s, so I get everything right the first time. Need all parts for a complete setup. Thank you