86 Motor in 68 Stang?

I'm in the middle of 67 ragtop Stang to a 68 Shelby tribute project. I'm in a bit of a fix. And boy do I need a fix!

I have an 86 EFI 5.0 but going carb with it. I read the distributor tech article on this site. What a great resource. Have to make gear change for this to work but it looks doable.

Question: 68 FW is too light for 86 motor. Appears the 86 FW won't fit C4 tranny.  The article doesn't reference a specific fix for this. Has anyone done this? I really need to know if the 157 tooth FW will fit the C4 housing? Also, I was confused a bit by the HB reference. Can I leave the 86 HB on the motor?

My tranny is a good ways from me so I can't check it out for a good while yet. If not the FW won't fit the housing...Do I have to get a new tranny. I am really getting an education. Learning more than I wanted to know...for sure.  

If you have the small bell (157T) C4, then you'll need a 50 in/oz 157T flexplate for an 86 5.0.  The large bell C4s typically use a 164T flexplate.  With the car being an early car, you should have the small bell on the trans.  You will also need the block plate that matches the bellhousing, otherwise your starter will be about 1/2" in the wrong place.  Bolt patterns for the block-to-bell are the same for the large and small bells.  
1967 Falcon 4 door 351C-4V
1970 Mustang 351C-2V
http://raceabilene.com/kelly/hotrod
Owner built, owner abused.

Hey F67,

I'm new to the group and had to reregister for some reason so I added the "1".

Much grass on the tips you gave me. So happy to make progress after some real challenges in other areas. Ordered 50oz 157T flexplate from Fordracing dealer. Also got the steel gear for distributor needed (found in M&F tech article). Found a source for the block
plate too. Maybe I"ll have this on the road before Jesus comes back!

Very glad to have found this website!!  

Many thanks buddy,

JS