Well I am impressed. That is some nice fabrication.
Question, since steps 4 and 5 seemed to solve your wind line isssue have you thought about removing the galv metal you added in step 3?
Also, since both the ROPS/roof and the chute blocker seem very well built and look good on your mower do you have any plans to paint them Gravely red or black?
If and when we decided the chute blocker is a permanent fixture, we will paint it. Most likely will not paint the galv sun roof.
Right now, we are thinking we should wait to hear the results on your chute blocker before putting much more effort into it.