ok so i know i could sit down and figure this one out for myself but thought it might be nice to have a team effort (if this results in me ending up with a better finish then i will suffer that  ) 
  
  
  
  
  
I bought a plenum spacer many many moons ago from another forum member.  The spacer came with somewhat less parts that it was supposed too   so for the time being I just cobbled together some bits and got it all sorted temporarily (im sure we all remember the cracked plenum fun).  so now i have a bit of time to get the car up to scratch i thought it was a good point to revisit the plenum spacer.  so the facts/issues: 
  
- it is a sloped solid aluminium spacer, 7mm back and 10mm front.  i found it once, i believe its an american one? but i cant remember what make it was, any ideas? 
- it didnt come with strut bar spacing washers or longer bolts so i resolved that finding some that fitted 
- it didnt come with a gasket so i liquid gasket'd it this weekend 
  
so the issues i have are: 
  
-air leak on 6 middle bolts, possible casues are 
--- the nylon spacers under the 6 towers are already squashed and now leak air round them 
--- the bolts supplied are just plain wrong, it was suplied with only bolts, no washers.  I have put rubber o-rings with washers onto them in an attempt to seal it but hasnt completely worked. 
--- the botls arent long enough in some places so i need new ones anyway, can anyone reccomend a supplier for them? and what type are reccomended, i assume ones suimilar to stock with a large flat head on them are best? 
--- is there somewhere i could buy new nylon spacers for the 6 bolts 
  
  
  
  
sorry to type so much but trying to describe it best i can. 
  
Cheers for any help/tips/links