Installing Radius Pickup in oval/round hole mandolin

I have a Brazilian bandolim, basically a flat top mandolin with a round sound hole. The sound is somewhat unique as they all are but the construction is conventional. I want to do an internal install of a Baggs Radius pickup.

The problem is that it has a small soundhole, too small for anyone's hand--about 2 1/4". I've tried the pickup various places on the exterior of the top with putty and it seems to sound best at either end just behind the bridge. The bridge is about 4 inches from the soundhole and there's two deep, transverse.ladder braces between the soundhole and the ideal location. The rear ladder brace is directly under the bridge. Putting the pup on the peg head side of the first brace is too microphonic when the top is tapped or touched (no floating finger rest), so it needs to be back further.

Just to make things more fun, it's devilishly difficult to see in there with a mirror because of the depth of the braces and the small sound hole.

How do I get that thing in there to glue it to the underside of the top? I'm thinking a bent rod holding the pup with putty on the back side, pushing the pup against the top with adhesive on the contact side, much like the K&K "bent nail" method for their mandolin pickups. The difference is that the K&K's go at the end of the bridge but right inside the F hole, where a bent nail can easily reach.

Does anyone have any suggestions?

Thanks,

Larry