Hot Rods suggestions shocks 40 Ford pu

coil overs Viking , ch***is eng. rear , ride is stiff .... any suggestions .....

 

I suggest you add a lot more information if you want an intelligible response.
Do you mean the front or rear is rough?
Solid front axle or IFS?
Engine - big bolck, small block
Do you kmow the current spring rate and shock rate?
When you say coil over, by definition it is a shock and spring combined unit. Coil Over Shock