9 inch rear question

[kwhite4]

I have a 9 inch out of a 66 f**d thats about a half inch from being the same lenth as the 10 bolt thats in my truck now.
I know Ill have to move the spring perches to make it work (leaf springs) but as I worked on last night I noticed that the pumkin doesent look centered.
Though this kinda wierd, the axles are the same length.
Anyone made this swap that might give me some insight on the offset of this axle. The axle is a factory 9 out of a 66 truck that I owned years ago, pulled this and went with a dana back then.

thanks
KW