@Gorke - A couple of years ago I disassembled my Heritage 90 to install bluetooth, so I have some photos and information that might help you.
First photo - This is the RJ12 (6pin) as it would be inserted in the Heritage and the pins as I measured them. Your colors of the wiring might differ from mine. Pin# is important.
Second photo - Top view of the board and connections.
Third photo - Voltage and signal measurements as the board is mounted in the case. Check to see that your voltages match up to mine.
Fourth photo - 4 pin connector to be used with bluetooth module.
Things you will need:
ASCOM Drivers: http://download.ascom-standards.org/ASCOMPlatform62.exe
Stellarium Software: http://www.stellarium.org/de/
Stellariumscope Software: http://welshdragoncomputing.ca/x/st/setup/Setup_StellariumScope_2016.12.26.exe
Driver for Heritage 90: In my attachments as zip file
Bluetooth HC-06 3.3v: http://www.ebay.de/itm/HC-06-Wireless-Bluetooth-Slave-Modul-fur-Arduino-RS232-/201448256635?hash=item2ee740747b:g:pFQAAOSwImRYbPZd
Connector 4pin (audio cable from old computer works well)
12v to 5v Power Converter (only when your bluetooth module can't be run with 3.3v): http://www.ebay.de/itm/DC-DC-5V-38V-to3-3V-6V-12V-24V-5A-Buck-StepDown-Konverter-Module-Car-Auto-Power-/131980745446?hash=item1ebaaa5ae6:g:4wEAAOSwys5WVbAO
1. When your bluetooth module is running at 3.3v. Insert the RJ12 into the socket with the other end free and each of the six wires stripped. Apply power (12v), check to see that pin #1 (+) and pin #2 (-) have 3.3v (roughly). Solder these to the respective connections on the 4 pin connector v+ and v- for the bluetooth module. Apply 12v to the scope and check to see that you have power to the bluetooth module.
2. When your bluetooth module is running at 5v. You will need to use pin #4 (12v) and pin #2 (gnd). Connect them to the power converter v+ (in) and v- (in). Connect v+ (out) and v- (out) to the bluetooth module repectively. Apply 12v to the scope and check to see that you have power to the bluetooth module.
3. If I remember correctly, pin #3 is TX. Connect that to RX on the bluetooth module. Pin #5 is RX. Connect that to TX on the bluetooth module. If it does not work, don't worry. Just reverse them on the module later. Important is TX>RX and RX>TX.
4. The HC-06 is delivered with pin code 1234 running at 9600 baud. If you want to change the pin you can use any terminal program and the command AT+PIN####. You will need a FTDI module to configure this.
5. IF YOU HAVE AN ANDROID PHONE (who doesn't). Download the Virtuoso App and you can test the scope functions now. Pair the devices, start the program, load the scope in the app, and test the signal. If it doesn't work, don't worry. Change the signal wires on the module.
6. FOR A PC: Install the driverAzGoto from the zip file first.
7. Install the Ascom Driver.
8. Install Stellarium.
9. Install Stellariumscope.
10. Start Stellarium. When it's finished, shut it down. It just needed to set up the config file.
11. Start Stellariumscope. Configure the telescope. Choose the "DriverAzGoto". You have to configure the driver now, gps coordinates, elevation, and so on. After this is complete, about 2/3 down in the Stellariumscope window is a button to send this information to Stellarium. Click and just keep clicking "Yes" in the next 3 or 4 windows. Restart Stellariumscope. Click the button in Stellariumscope to start Stellarium.
12. You will need to go through the settings to set up your location and everything, and the last thing is to find the telescope plugin and click "load at startup". Shut down Stellarium, and shut down Stellariumscope.
13. Restart Stellariumscope, and restart Stellarium. Go back to the telescope plugin and click "configure". If there are already three scopes listed in this window, you are done. If not, click on add and in the next window click on "external software or remote pc". Shut everything down, restart, check for the scopes in the plugin. If they are there (sync, cancel, scope) then you are good.
I used the 5v variant.
If I missed anything, let me know.
Have a good night.
DriverAzGotoByArmazemDoTelescopioSetup.zip