Here I show the installation of a deck pickup including a preamp for the end jack. 

If you play not only alone in the living room on the couch or in front of a silent auditorium, you can not avoid amplification.
The more valuable the guitar, the more important it is to keep it in its original condition as much as possible - i.e. not to drill holes in the sides, etc. Only what is the solution?

Endpin preamps are the best solution here. These contain the active electronics on a circuit board, which are mounted together with the book for the connection cable. Power supply comes from a battery, which is attached to the interior of the guitar (for example, on clips or in small pockets).
The pickup is often located directly under the bridge. But there are also those that are simply glued to the top (contact pickups).

From the Finnish company B-Band there is such a variant with a top pickup (AST 1470) whose installation I show here. The A1N has to create feedback resistance at 180 Hz an attenuation of the signal by 6dB. I found the sound quite convincing. Compared to the standard A1, there was nothing wrong with the 180Hz adjustment.

There are a few tricks involved and there is also the risk of damaging your good piece - if you are unsure, please leave it to an experienced guitar maker.

Marking and drilling the hole for the pipe bushing booster.

Determine the pickup position and where the battery holder belongs. This must be easily accessible - even with large fingers. The cable still long enough.

You can get there well here, you are also not too much in the vibration range of the floor. The manufacturer promises about 750h operating time.

The pickup is placed under the ceiling and controlled.

Before everything is assembled, one more function test.

Then the assembly and when the strings are reassembled and tuned, you're ready to go.