Is there anything else i'm going to regret not doing after i finish this?
Also should i do it in cab, pull the cab or pull the motor? i have access to lifts and cherri pickers.
My vote is to pull the motor since you are interested in putting a set of lifters in it. The 300 bucks or so for the set of lifters is going to be the best peace of mind since you are getting up there in mileage. With the motor out the rear cover only takes a few minutes to pull off to get to the rear lifters. Doesn't make sense to pull the cab and then pull the trans. Once the motor is out you can get it away from your truck where you don't have to worry about damaging fenders or being cramped up in the engine bay if you were to do it in cab. Engine removal is fairly easy.
I see that you are going to reseal the ipr valve (good idea) as well the hpop cover since it will be off, a 5c3z-9g804-c comes with the ipr screen kit, the black and yellow hpop o rings, the blue o-ring around the top of the pump and the hpop cover gasket.
reseal upper and lower oil pan gaskets and pick up tube o-ring as well. Another plus when pulling the motor.
I would put a new MOTORCRAFT thermostat in it and pull the water pump to inspect the front cover and water pump fins. 4c3z-8507-aa is the part number for the water pump oring. You are also going to need a 3c3z-6619-fa to reseal the lpop cover gasket since you are removing the front cover.
