PERC 6I replacement for R410

Dear all,

I m having a hard time searching for this subject although I consider myself good at mining information before asking in a forum.
I have a couple of R710s in my office and an R410 which was bought used. This R410 has its PCI x16 slot populated with a Perc 6i card, underneath it, there is the iDRAC Express. The machine also has iDRAC Enterprise fitted. I really dont know what the recycler I bought it from was thinking..
This is a server I want to use as a test rig. It currently runs Server 2012 r2 Essentials with Workstation Pro to emulate some scenarios I m working on.

1)I want to free up the x16 slot in order to accomodate a single slot gpu and give the poor VMs a little help with graphics.
Since this is not a production machine and I really don't care much about the raid array speed, can I replace my Perc 6i with the HM030 which I see on some pictures on the internet that goes below, on the x4 slot?
2) When you change the card to the smaller HM030, I see (from pictures) that I will need a new cable that goes from the riser to the two points on the backplane. (Like a mini sas Y splitter?, Excuse my ignorance)  Does anyone know the part number for this?
3) Is it ok to remove the iDrac Express and just leave the Enterprise on?

Thank you very much in advance.

Antonis