you can connect any model directv receiver with a swm8 however you may not use the swm lnb. Reason being you would be using two multi-switches which is a no-no. The concept is to use the swm 8 like a wb68 switch, i.e. it has 6 inputs 4 which are commonly found on any ka/ku multiswitch with two flex ports. Flex ports are only used with multiple dishes. The outputs of the swm8 are for swm splitters and the swm port 1 is where the power inserter is located. You still may only hook up 8 tuners to the swm ports but if not using swm port 2 it must be terminated. The 3 legacy ports will not pass signals from the 99 and the 103 satellites so it would act like a 3 lnb (101, 110, 119) which makes sense because if it is not a swm receiver then it won't take those two satellites anyway
This is not a normal install but who wants to get rid of their TIVOS?