Help Identifying '90 GMC 1/2 Ton Steering Box
 

Dear Friends,
I need to ID the steering box on my '90 GMC pickup so that I can buy a rebuilding kit. Here are pix of all the markings on the box. It seem to be a 700 or 800 Saginaw. The truck originally had a V6 but it's been swapped for a 350 so perhaps the steering box also has been swapped. If you can ID this box please also let me know your sources for future references.

Attachment 1063

Attachment 1064

Attachment 1065