Fresh V-8 build, wanting advise
 

So as the title suggests, I procured a FC with most of the swap done. I am trying to figure out what I can do on a budget to help make it a DD/ fun cruiser.

Basic info:
350 Vortec (96+) W/ HEI ignition
High rise intake
650 Holley Double Pumper w/ mechanical secondary
T-5 Trans
Stock 4.10 rear end

It was to good of a vehicle to just turn away from when I bought it. Body is in great shape.

The rear end is my concern. But I don't know a lot about them. Would like to keep my IRS if all possible.

It largely depends on what type of FC you managed to get. You'd be fine with the tii rear but not so much the n/a. You can purchase the parts to swap them if needs be but then you'll need a different flange for the driveshaft. You can all purchase an 8.8 IRS out of a ford (cobra or exploder, be VERY careful purchasing an exploder diff, they tend to be poorly manufactured) and some mounts and swap that over.

Were there different gear ratios that came in those rearends? 3.73 or 3.55bis what I'm aiming for.

Those rear gear ratios are not available. You will need to do a Ronin Speedworks Ford IRS 8.8 swap to get a 3.73 or 3.55.

That kit mates a Ford 8.8 out of a 02-05 Explorer to the factory rear suspension.

Where can I find the ronin kit? Is it in the vendor section here?

They are a vendor here. Roninspeedworks.com.

I have their kit in my car and it is awesome.

+1 on their kit. I have it in my FD and it is awesome. Was a very easy swap. Did it in one day.