I don't know about your fan. My 99 don't not have the rad. that Flexilite say it should have. I had to buy another. You can buy a controller for them I would think at a local parts house. My fan is mounted with push thought tie straps on the top and has brackets on the bottom. I can get pictures of it tonight if you want.
1999 Silverado 1500 Ext. cab Red 2/4 hotchkis drop & swaybars, bilstein stocks, AR626 & 404 Nitto's, Yank converter, ASM headers, ASP underdrive pulley, Taylor wires , free mods VCN 2000, Nelson Performance tuning
2002 Red WS6 M6; Flow master K&N