I have the same tank in my "61" ,it fits the truck frame but not an exact fit for the Burb http://www.summitracing.com/parts/CLP-6366FMT-K/.Issue on my K-10 is the frame height appears to be a little taller than the truck creating an interfearance with the frame rail,I have not made the permanent solution yet .Price was right ,came with sender as well holds 20 gallon

In the works 2006 GEN III 6.0 /4L80E/ 205 New process,A/C and power brakes .