You CAN switch to an F350 front suspension but you probably don't need to. The IFS front end is fine (you don't say in your sig if you have regular or super cab, so I don't know which you have) if you're not rock crawling. It has nicer ride when you're not plowing, too.
1992 F250 XLT 4x4 Super Cab 7.3 IDI E40D 3.55 ATS 088 4"R.C 360k
1982 MBZ 300SD W126 California model w/Sunroof, no EGR