C6100 LFF and SFF interoperability

So we have a cluster of 12 C6100 [LFF L5520] (32 nodes) in production in suites in the US and Europe.

We have only dealt with the LFF models up to this point.

Today I acquired a SFF model [SFF e5606] (4 nodes) {service code 6DH4TR1} today, and they all have the LSI 9260-8i SAS/SATA Cards.

Please excuse my inexperience in this question, but we have never dealt with this model or this card before, none of our LFFs have a RAID card.

1) am I correct in assuming that the nodes are all interchangeable? i.e. I could install one of the nodes with the RAID card and the e5606 in a LFF chassis, and vice versa, I could install one of the L5520 nodes in this SFF chassis.

2) is the backplane on this SFF model standard, or is it specifically configured/reconfigured for the LSI cards?  I know it supports 24 2.5" SAS/SATA drives where as my LFFs support 12 3.5" drives (6 vs 3 per blade).

3) again, I apologize for my inexperience, but if the backplane is standard, I can install a combination of SAS and SATA, correct?

4) if I were to REMOVE the LSI card from any of these blades, can I assume I would just reconnect the blue cables to the motherboard, rather than to the riser card?

Thanks for helping someone who is a newb at the SFF model!

Andy in CO