[Tigers] Bumper installation

[Rollright at aol.com]

Hello,
 
Last night, Tod Brown and  went over the fixing bolts for the bumpers.  A 
couple of issues/questions arose.
 
1) the bumper to chassis fixing bolts for the rear are listed as  1/2" X 1 
3/4 UNF. For the front it lists a
 screw (?) of 1/2" X 1" UNF. Bolt for one, and screw for another?  Dim 
memory tells me the difference between a screw and a bolt is the a  screw is 
threaded up to the head, and a bolt has an unthreaded section between  the 
threads and the head. Also, how come the difference in  length here?
 
2) As I'm trying to assemble a complete set of front and rear  bumpers with 
everything, ready to bolt on when I take off the old. There is an  odd part 
that must have some connection with the bumper system as I found it in  
that box in the basement. It is a slug of aluminum (?) cylindrical (very  
slightly barrel shaped) 1/2" tall, 1" in diameter with about a 1/2" hole  drilled 
out of the center. Is this a bumper system part? Where does it go? 
Seems like a spacer.
 
Best to all,  

Jim  Armstrong
Mk 1A  
382002083
LRXFE