COMPLIMENTS OF MARTY, N9BMH
Mod to add Great AM receive on Icom 706MK2G
This mod requires you work with surface mount parts. Be sure you use an iso-tip soldering iron or a soldering iron that is esd proof and grounded.
Purchase the filter # FL-102 from Icom. This filter is used on IC-775dsp.Remove the main board from the radio (the board with the IF filter). Be sure to mark all the cables. Flip board over and locate Q2224 and Q2222.
Lift pin 4+5 on Q2224.  Lift pin 4 of Q2222. Attach wire (30 GA) from pin 4 of Q2222 (The transistor itself- not pcb), To pad #4 of Q2224(pcb). Insulate the transistor leg Q2222 from board. Install filter in the slot farthest from the original filter. It would pay to have a service manual for this radio to find the location of these parts. Put board back in radio... insure all the cables are properly seated.
To use this mod, do not modify the menus or set any thing different. You will still have narrow AM if you want it by pushing the narrow filter button on the front panel.
Enjoy N9BMH Marty
 
K9KJP`s  706MK2G AM MOD SUGGESTIONS
I started doing the mod and found it was pretty easy to hurt the transistors trying to lift them.  I settled on cutting a couple traces and soldering to the transistor (Q2222) and to the pcb on a through hole pad.  Make sure to use a small (very small) flat bladed screwdriver to scrape the coating from the through hole in the pc board.  BE VERY CARFULL WHEN CUTTING TRACES AND SCRAPING THE COATING OFF THE BOARD.  I just found doing it this way was easier for me and the chances of hurting any components is about nil.  It can also be easily reversed by scraping the cut traces and soldering a tiny wire to reconnect them and removing the jumper.  Either way works.  These parts are tiny so take it slow...
73,
Kevin, K9KJP
 
 
The mod for the agc is to remove C775 (10 mF) and replace with a 3.3 or about.
This mod will take the recover time from 3 seconds to about 1 second.