Ok then to start with the 5 clutch top gear your best start point is to use a factory hub with 4 clutches.These have the circlip groove down from the top edge at 1.025".With this drum you use 5 clutches @.078" + 5
[email protected]".With this setup i have used the original .340" pressure plate and machined it down to a total thickness of .260" then machined a step for the snap ring at approx .175"-.185" depending on the final clearance of .025"-.035".
The best way to describe to machine the p/plate is to look at the bevelled plate from the forward clutch hub that goes against the piston and your plate should look similar but with a thicker edge.You can also use one of these fwd plates as the top p/plate but you will have to pack up the clutch clearance with a thicker snapring or oversize steels as the step on this plate is only .125".I prefer to machine my own plates as it leaves them a little thicker for added strength, though it prob doesn't matter as some of the aftermarket kits use a pressure plate listed at .125"-.128".
There are other methods using .062" clutches and .060"steels or combinations of .060"steels and .078" clutches that can fit 5 clutches into the original 3 clutch hubs.There is an 'ALTO'brand kit that you can use without machining and i have the part no. if you need it. I suppose this is getting pretty confusing by now but if you know what top gear hub you have we can come up with a solution.
I have used a mod in the past for the number 9 thrust that puts an oil feed direct to the thrust washer .I am currently working on my own roller c6 and for the number 9 thrust i'm pretty sure i will be able to use the same roller bearings that i use for c4's.The bearing is from a turbo 350 originally.
A few other things that you will be needing is make sure that you have a 5 clutch forward hub.The diaphram spring disc against the fwd piston there are 2 thicknesses.(.078"+.094")I like to use the thicker one.
Also a 5 clutch low/reverse clutch pack too.(Some only have 4 in low/reverse but you can go to 5 or even 6 in some cases)
Use a flex intermediate band with a kevlar lining.For the servo i prefer the 'L' or 'D'.The 'D' is an alloy piston with o'rings so is reusable.The "R" is the factory high performance one but i haven't tried that one ,though most sources say this is the go.
For the valve body i like the transgo 67-2 kits that keep the auto shifts in drive.Also if you can get a pan from a bronco that will give you extra oil capacity.There are 3 different depth pans that i have come across but be sure that you get the correct filter to match whatever pan you're using.
That's all i can think of for now.Any questions just ask and i'll help if i can.Who knows,the c6 post might become as popular as some of the c4 ones...