Undertake it or not. But I would hesitate to assign blame to overheating
at this point.It seems a logical assumption, but it could be a myriad of reasons why it overheated... like have either of these guys inspected the backside of the points cover to determine whether something was rubbing?
Bill Benton just had a Dyna fail during a super hot race weekend, not because of ambient heat, but due to friction. It only manifested itself because it was super hot outside
also.If memory serves, the 650 C5 was a recent addition to Paul's product line-up when these were bought. I doubt the coils are heat susceptible, because they appear to be like his older units, and not the newer type. Those other units were in use for many years without reported, regular failure. Just saying...
But, if I were to attempt to ascertain the issue, I'd ride as is until it failed. Then, remove the cover, and see if it fails again. If not, then, you're on the right trail. Obviously a digital thermo in the pocket to take a cover reading, a plate reading and a block reading at the point of failure would be helpful.
It would also be extremely helpful to get some voltage readings
when it fails. Is there a drop in VDC at the coils, is there a resistance build-up, etc? See where I am going?
If you do make a ventilated cover, few, small holes in the upper/leading half would be all I'd make, but I would create a drain "slot" in the bottom for any moisture that might infiltrate to escape after riding, or standing still. Adding rain to electronics is the 2nd worst idea after heat