how can i tell the difference beween an ifs and old front driveshaft?
 

someone gave me a front shaft but was unsure of the year or anything else about it.he says he thinks its an older solid axle shaft but is not sure.i dont have the slipyoke end but by looking at it it looks just like the ifs one i modified for my front.it has that sleeve on the shaft that slides over the slip part and it appears to be the same length.i only need the cv part of it to extend my regular ds.it seems to have a lot of droop but i can also see that it is hitting the grease fittings hard inside.

SFA fron drivelines have a 30 degree CV, IFS trucks have a 20 degree CV.

this looks like it will go 30 but i think its because its severely worn.are there any distinct differences i can see?bolt pattern maybe?