Definately do it yourself . Easy as hell . Just keep an eye out when jacking up the body > look out for wires stretching and anything coming in contact with the body that didn't before . I've prolly put on about 10-15 in my day but recently have become too lazy and just take em to the shop .

FWIW > Hi-Rust charged me $235 to install a 3" on a 97 F-150 a few years back and that was including the price of the lift . ( but I also bought 35" BFG's and 16.5X9.75 Weld's , too so it may have been a package deal )