AWS blower combine or header mount ???

[two rotors rule]

On a 9040 CR with a 740 cf 25 ft header which is better, to have the blower mounted and driven beside cab on combine or on the header.
Also single knife drive vs. double drive which is better.
Thank's for the input.

[tx68]

I have a TX68 with a 30 foot 973 head with double knife drive and head mounted fan for the AWS air reel.
First I like the double drive because it makes handling the knives much
easier and I think it is much less stress on the wobble boxes. Never had
any problems with it other than regular maintenance. 12000 acres through
it so far.
It would be very difficult to mount the AWS fan to this combine so mine is on the header. This is nice because it does not clutter up the combine with the extra hardware of the blower and belts.
The blower is all belt drive which is cheaper to rebuild than a gearbox.
Just a bunch of bearings, shafts and 3 belts. Main thing to watch on the
blower is chaff in the fan needs cleaned out often so it does not vibrate.
The vibration shakes all the bolts loose in the blower drive assembly.