Why do you believe you need Jumbo Frames? A jumbo frame is like sending multilpe frames together one way. This reduces other computers from communicating while that packet is being sent.
Image traffic. You have car every so often, enough that in between the next car you have time to pull out and get in traffic. That's a normal frame.
A jumbo frame would be sitting there while 4-5 cars passed and before you had an opporunity to get into traffic. While traffic is moving along, others have to wait longer.
Now if you were constantly transferring a lot of files from point A to B, and then back from B to A, it might help a little.
If you don't spend at least a quarter of your day transferring gigs of data between computers, it is kind of over kill.
You could set up jumbo frames internally and the other NIC to send normal packets for the internet. That adds another lay of complexity as well.