What shims??..i've installed tti's on 2 different '70 dusters no shims needed..they went in NO PROBLEM!!! and i can change all the spark plugs and the starter if need be in less then 15 minutes,can't say that about any other brand..theres those that own tti's and those that wish they did!!!..As far as comparing the price of having a custom set of headers made..last time i checked it was about $1000.00..thats about $400.00 more then what i paid for tti's...
