Eternabond over or under vent cover mounting brackets?

[MILover]

DH and I have decided to do some preventative maintenance on our roof using Eternabond tape. We also have a Fantastic Fan vent cover that needs to be installed. We're hoping that those of you who are experienced will chime in.

Should we:
1) Install the vent cover mounting brackets directly onto the existing lap sealant, then use Eternabond tape over/around the base of the brackets? My concern is that the vent cover won't last forever, and if the company ever changes the style of mounting brackets, we'll then need to rip off the Eternabond to remove the brackets...

OR

2) Eternabond over the lap sealant, then screw the mounting brackets into the Eternabond tape-covered lap sealant, and use a dab of Dicor to seal the screw entry holes? The concern here is that we compromise the Eternabond seal by putting screws through it.

Thanks!

[KingFisher]

I put a maxx air cover over my fan. The brackets screwed/bolted into the curb. I don't think I'd want to install a fan cover that has to screw into the roof.

Not an answer to your question but something to consider.

[MILover]

I may have worded that poorly. Husband says that he needs to use the existing screws for the vent on our roof, to install the Fantastic Fan Cover mounting brackets? I thought he could just clip it on too, but he says no... So, he'll be using the existing screw holes, which complicates things further if we put Eternabond over them...