Does one just butt weld the boxing plates to the frame or does one bevel the edge of the frame and plates and sent the plates in just the width of the boxing material. Just took the flathead V-8 out of my 47 and getting ready to do a Mustang II IFS, will be trying to install my 82 granada rear end. All this for my 302- C4 combo.

 

I have read that you can do either but beveling the edges and welding usually looks better. I decided to go with the beveling idea and havent finished yet, but found that my MII crossmember would have fit better if I had butt welded them. I am just going to "shim" the MII and leave it at that. Good luck

 

There are several alternatives to "boxing" your rails.
I "in-set" my boxing plates 1/8th" into the frame rails, welded them solid and then"beveled" (rounded ) the welds on my 46, Pete & Jakes shop started this with their 32 frame rails, I am pleased with my results.
Butt welding works just as well, do believe it is more work though.

 

i always go point to point,wind up the hot glue gun so u get 70 % penetration or better and always move around the frame so as to lesson the chance of distortion, u can't go wrong ( normaly!)
cya..,.gary