Flail Mower HELP.....Have an IH 71 Flail..minimum HP, weight?

[ricksalisbury01]

I just bought an IH 71 Flail mower. The owner said that it was a 6 foot cut....but when I loaded it on my trailer, the housing was about eight feet long. Any Ideas as to the minimum horse power needed, and the weight of this flail mower? I have about 28hp at the PTO (I am concerned this is a little light) and lift of 1764lbs two feet aft of rear hitch on the three pt.
I can not find any info anywhere online.
Thanks in advance!!!!