The 132" wheel base trucks from 68-73m and all 76+ FSJ's are different. 57" eye to eye with the pin offset forward 5".
The years I mentioned in my above post are 52" eye to eye with a centered pin, 26" from pin to eye (front and rear) just like the M715's.
Civilian front springs are different though for all years AFAIK. Certainly on teh trucks, or I'd be running M715 springs there as well.
Here are BJ's springs, you can buy them seperately.
For some reason I can't right click to copy the link for luft kits, but here is the link to thier suspension section. They don't list the early springs seperately, but have mentioned in the past they sell them that way.
http://www.bjsoffroad.com/cartgenie/...sp?category=14