Can you be more specific about what you wish to do with an MC-808?..
For example, If you connect the MC-808 via midi to your computer you can:
In the MC-808go into system>sequencer; set sync mode = slave
In SonarPreferences > Midi > Devices; enable both input and output for your midi connection to the MC-808
Preferences > Project > Midi ; check "send midi start/continue/stop/clock"
Preferences > Project > Midi ; check "midi sync output ports" for the port to your MC-808
With this setup
1. your mc-808 will run locked to the Sonar clock and respond to sonar start/stop etc
2. you can use any midi input or create midi source data in Sonar and use the MC-808 as a sound generator
3. you can record MC-808 patterns into Sonar (provided you enable ext seq out per part in MC-808)
then, connect the MC-808 via audio to your interface and you can record your MC-808 into a Sonar project.
Use a similar approach for your synth...