After some mock up work I found the new "shroud" to be pretty unusable. The expanding left it very unconcentric and trying to smooth it out was next to impossible with simple hand tools. 16ga is nothing to mess with when you can't get enough leverage to work it... I ordered a couple of 4 to 3 1/2" reducers from Speedway. I also bit the bullet and ordered a tubing expander kit from Lisle. This will come in handy for exhaust work anyway and it does have a role in this kind of fab work also.
After dinking around with the shroud mess for a few hours I called it a lost cause. I set up the new, larger adapter plate in the mill and got some work done on that. Making the hole patterns, trimming out the blank and machining it round just like the previous one.
https://images12.fotki.com/v539/phot...MVC002F-vi.jpg
Holes drilled and c'bored.
https://images59.fotki.com/v1640/pho...MVC003F-vi.jpg
I'll be milling an angle on the back side of the adapter to reduce the diameter to better match the shift unit.
This is the back side I will be milling. The pencil line is the size of the shifter unit.
https://images40.fotki.com/v20/photo...MVC005F-vi.jpg
Setting up the rotary table in the mill I needed an adapter to locate the plate concentric to the center of the rotary table. I machined this out of a piece of 1" diameter aluminum stock.
https://images15.fotki.com/v246/phot...MVC016F-vi.jpg
The larger end pilots in the center bore of the table and the small end pilots into the center hole of the plate. I used a long bolt and a couple of spacers to mount the plate to the table.
https://images54.fotki.com/v1642/pho...VC002F1-vi.jpg
After getting the piece aligned in the mill I tipped the mill head so I could cut the 40 degree angle I needed. Sad to say I could only tip the head about 32 degrees because of the Frankenmills' questionable construction...
https://images47.fotki.com/v826/phot...MVC006F-vi.jpg
I got both back angles milled. Not as steep as I was planning but I think they will work.
https://images12.fotki.com/v1641/pho...MVC012F-vi.jpg
https://images47.fotki.com/v826/phot...MVC003F-vi.jpg
I mocked up the adapter plate and I think it will look better then the previous attempt.
https://images15.fotki.com/v398/phot...VC006F1-vi.jpg
It should look great after some cleanup and satin black paint.
https://images15.fotki.com/v398/phot...VC007F1-vi.jpg