I just purchased a dana 60 and 14 bolt out of a 1 ton chevy for my k5 and was wondering if i have to change the spring perches? I heard that the axles will bolt right in with bigger u bolt,then i was told that they wont bolt in with out modifications im confused?Is 3/4 ton and 1 ton's have the same perches as a k5?  

If they are out of the same generation chassis they will bolt in. A rear axle for a 88 on will not bolt right in.  

Someone told me the dana 60 front is the same but the 1 ton 14bolt rear has wider perches? im not sure if there right on that tho i guess ill have to measure to be safe,the are from the same year tho  

Being that a HD CP6 2500 has exact same frame as a 3500 I see no issues. Up until 88 1/2 tons and 3/4 tons shared frame styles. Now a dualie axle might have different perches but a SRW should not.  

The 60 will bolt in but you need 2 get a 14 bolt out of a 3/4 ton and it will work fine.But with my blazer with a 4" spring lift i had 2 get my 14bolt rotated 2 get a better drive shaft angel and lowerd tcases about an inch.