Well, Mr. Carty choose to model the 707-420 which was a produced for BOAC only version of the 707. Mechanically it differs from the more common 300 series we are familiar with. The fuel tank arraingement is different. If you attempt to use that panel with a 707 300 series from HJG engine 2 and 3 will not run or start because the panel will think they are being fuel starved. Also, the flap positions are slightly different and the A/P is to because the HJG aircraft.cfg was set up to fly under the default 744 panel. Also, I would recommend writing into the aircraft.cfg of the HJG aircraft the electrical entries from Carty's model. So, here it is. If you aren't afraid to tackle it and you can type ok and have patience, download whatever 707 you fancy from HJG. Open the aircraft.cfg of both the Carty model and the HJG model and copying from Carty's aircraft.cfg change these entries in the HJG aircraft.cfg.
1. Fuel
2. Flaps
3. Radios
4. Autopilot
5. Add the electrical entries from Carty's aircraft into the HJG aircraft. You can type that section in anywhere you please, it won't matter. Just copy away. After you have the editing done if you wish you can save yourself having to do that again. When you download any additional 707's from HJG Just move the texture files over to your original HJG 707 folder, open the aircraft.cfg and under the intitial [fltsim] entries at the top just add on under that, [fltsim0,1,2], however many liveries you have etc. and then copy over from the 707 you're adding the textures from. It's still editing but a whole lot less lines than the initial edit ;-)
PS:
www.simufly.com/hjg/Biggest collection of 707 and DC-8 models on the net. Enjoy