I just did this as my 6th cylinder exhaust lifter froze up. I used a Melling MTC-7 with spring upgrade. its a class 1 cam, designed for stock tune. its been tuned as of yesterday, the idle was a little off and would stall sometimes, it did run better under 91/93 octane on a 91 tune with my predator diablo it ran just about 10% lean, within range but the longer opening adds more air to the combustion. I did mine over 3 weeks as I didnt have any idea what went wrong and it was 10 degrees in the garage, I only worked at nights. I ran into a few problems with stripped bolts and threads. I'd recommend while you are in there, you have to remove the oil pump and timing gear, replace it. One take away I had was the install of the oil pump. I didnt notice nor was tehre any documentation of the 'dimples' on the gerotor gear in the pump as you assemble it, make sure the 'dimples' are facing you. I didnt know this and I'm hoping they are out and if not, it doesnt hurt! I also replaced, cam sensor, oil pressure switch, engine coolant and MAP sensor. I also cleaned my throttle body, air intake housing, injectors, dropped in new plugs and new water pump.
I think this could be done in a weekend easily, just have an extra set of hands, all the tools/parts there, I'd order all the parts i mentioned, then return what you dont use. I have the service manual in PDF form, it did help with some of the procedures, sequences and torques.
