T310 upgrade disks and raid controller from Perc 6/i to H700

I have a cabled T310 with a Perc 6/i and 4 x 500GB drives in a raid 10 arrangement and will be replacing them with a H700 controller and 4 x 2TB drives.

Firstly there is cabling issues. I cannot seem to find the right combined cable for the mini SAS to 4 x SATA together with a power cable that plugs into the 8pin P2 power socket. I have ordered a Y690K cable which has the mini SAS to SATA connectors and a 12pin connector that includes the orange 3.3V cable for resetting the drives (but I do not need). However I am having to makeup a molex interconnector cable to link the 8pin to 12pin for the 5V and 12V power to get around this problem. Unless somebody knows about another cable that is available somewhere and not discontinued or priced more than the cost or a new server.

Secondly there is a 4pin 2 wire connector from the motherboard to the Perc 6/i which is described as 'disk active'. I do not see a suitable header on the H700 to plug this into. Bear in mind this is a cable hard drive version and not a hot swap setup where the disk active cable is usually plugged into the hot swap back board. Is there a header on the H700 I can use or does somebody have a document that explains what each header is for ?

Once the cabling is sorted out my final issue is with the disk upgrade. Should I do;

1 - Replace one disk at a time and have the system repair the raid each time whilst the drives are still connected to the Perc 6/i then swap the controller for the H700. I know that this will take some time to do but the system will be available most of the time during this upgrade. 

or 

2 - Use a bare metal backup solution to take a copy of the Perc 6/i raid 10 volume then swap the controller card and disks over then do a bare metal restore. I believe Acronis have a bare metal backup version that can handle restoring to dissimilar hardware. Although longer it does provide me with a easy fall back if things go wrong.

Any thoughts on these issues would be most helpful.

Thanks in advance.