Early A V8 swap advice

This winter I plan to start on my 1965 valiant 100 project. I plan to swap out the three on the tree for 4 on the floor and to bolt that to my '68 340. I have a few questions about parts required and was hoping to draw on the experiences of those of you who have done it.
I'll start with my list of questions and if any of you know of anything I missed or have any advice about what parts to use or avoid, I'd love to hear it.

1) How much fire wall/toe board modification is required to use a 10 1/2" clutch bell housing? I have a bell for a '73 340.

2) I know the K frame is the same on these cars for /6 and V8 but exactly what engine mounts do I need? Both on the block and the K frame.

3) Although I love the look of fender well headers, I want under chassis headers. (I'm looking to be able to carve corners). Are TTI and Dougs my only options here? If so, what are the pros and cons of each? Do any of you have under car pictures of your exhaust systems with these headers? I can custom bend pipes at work, I'd just like an idea of whats going to need to happen down there. I will be modifying a spool type trans mount for dual exhaust clearance.

4) Do I need a specific V8 throttle pedal? Is there a throttle pedal that will match the interior but convert to a cable so I can eliminate the solid linkage or can the existing pedal be modified for a cable?

5) I will be relocating the rear spring front mounts. Any idea on width and offset of the rear tires with this modification? I have an A-Body 8 3/4 that will remain stock width and will stay small bolt drum. I am converting the 9" front drums to Kelsey Hayes disk. I have everything except the front hubs. Anyone have a pair of front hubs they would be willing to sell?

6) Should I go with a factory disk proportioning valve or an adjustable aftermarket? (I'm leaning towards aftermarket for tunability).

7) Seat covers and headliner. Are they available for these cars?

8) I have the drop v8 center link, V8 torsion bars, & a sway bar kit for the front. Is there anything else you know of that I might need chassis wise for this swap?

9) Have any of you assembled the K frame with the under chassis headers and set the car down on the frame like in the factory? I'm thinking that might be the way to go considering the tight quarters.

Like I said, If you have any advice or know of any additional parts I will need please feel free to let me know.

Also, If any of you need my 3 speed, the column linkage, or the drive shaft, let me know. I also have a new in the box never opened carpet set from ACC that came with the car that I will not be using. I believe its black.