Oops rivet on elevator stiffener trailing edge

While drilling one of the unpunched aft most stiffener holes in my elevator using the skin as a drill guide, I elongated a hole to approximately 7/64ths. I was planning on drilling it up to round using an approximately 7/64 drill bit and using a half size (7/64th) oops rivet (https://www.flyboyaccessories.com/product-p/3501.htm). I know this is an area with cracking issues and I am not thrilled about using an oops rivet here. Here are my questions.

1) Will a 7/64th oops rivet adequately secure the end of this stiffener? Similar to a standard -3 oops rivet, the head is diameter is slightly larger (0.008in greater) than a standard -3 rivet head.
2) Will I be able to get the shop head height flat enough not to rub the rivet on the stiffener above it?
2) Should I just use a -4 rivet despite the aesthetic issue? Same question on shop head height.

Oops rivet

Proseal the stiffeners before riveting. Just a thin amount as a bonding agent, not like the amount used for sealing tanks. Then use the Oops rivet. I prosealed the stiffeners on all my control surfaces.

I plan on prosealing between the stiffeners. Are you saying run a bead of proseal under each stiffener or just under this rivet? Can I use a 30 minute epoxy instead. Also will the primer affect adhesion?

If you choose to glue it down, a rubbery type (proseal of similar) adhesive would be better than something that dries brittle.

I cant imagine noticing if a rivet was a 3 or 4 at that location. I have used the oops rivets and have reservations about how strong they are with the reduced head-shaft ratio. I would use the larger rivet. The 3-m epoxy or proseal is also a good idea. If you just rub a bit of primer around the head just before painting, it will disappear and it will be strong.

The main question that I have with the -4 rivet is whether the shop head will be low enough to clear the rivet above it at the folded trailing edge.

Proseal

RV701775 said:

I plan on prosealing between the stiffeners. Are you saying run a bead of proseal under each stiffener or just under this rivet? Can I use a 30 minute epoxy instead. Also will the primer affect adhesion?

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I fay sealed mine. Super thin application on each surface the entire length. Cleko and rivet. So thin it doesn't squeeze out the edge. Also add a dollop at the aft intersection of the oais of stiffeners.
Check the aft shop heads before closing up and make sure they clear each other.

RV701775 said:

The main question that I have with the -4 rivet is whether the shop head will be low enough to clear the rivet above it at the folded trailing edge.

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As long as it is dimpled properly, it should be fine. If you have to, you could always sand or shave it off a bit. Either way, nobody but you will know about that rivet.

To the original question, I would just simply use a #40 rivet but a little bit longer one. On the trailing edge of the rudder, we are pounding the shop head to make it look like the flat head. This will swell the rivet enough to fill any extra space in the elongated hole.

The problem with the oops rivet on the trailing edge is that the head is of a #40 but the stem is of a #30 rivet which requires more force and more pounding to get it flushed on the shop head. This extra pounding could easily cause your trailing edge not to be straight, not to mention that the shop head portion would look really weird.

Hope this helps.