So you have 4 cables 2 from each lnb ?
Or 1 cable from each lnb ?
If it is one cable from each lnb you could only say whatch 1 channel on thor and record one on sirius or the other way around.
You can not record and watch channel from the same sat unless there on the same transponder.
Your also going to need to use both tuners to achieve this leaving out the switch.