problem with lift springs and shackles

[ontariobluenoser]

Need some advise hope someone can help
I bought a rough country 6" lift kit springs frt and rear and 2.5" ord
shackle flip kit for the rear
Installed the kit yesterday frt went ok but the problem is
with the rear. I mounted the ord flip kit as far forward
on the frame as poss made sure it was in the correct direction and the fat part of the 52" spring was at the rear but when I went to attach the stock shackle to the spring the shackle is basically just an extension of the spring
The wheel base of the truck is now 4" less. Tires sit forward too much.
I talked to jamie at national 4wd and he is going to check with
Rough Country on monday. Do I have the wrong spring length or??????
Truck is 80 k10 350/700r4/np205 combo long box.
Any help will be appreciated and yes this my first. tks rob
Sorry no pics avail as of yet