I installed coated Hedman long tubes from Summit on my 88, and they fit perfectly. Only required that the starter, oil filter and plugs be removed to install. The downside to these headers is that the were rather pricey. 450 bones and took about a month to get them, apparently they don't keep headers for a K3500 with a 454 in stock, they make them as needed. The install depends on what a person thinks is easy or hard , I feel that for what was gained, (under hood temps went way down and also got a slight increase in MPG) the installation was easy. I have installed headers on other rides that I wished that I had never even started. Long tubes for sure.