[Bender]

Steve.
Its always best practice to fit new lifter when fitting a new cam. Depending the mileage on the current lifters. The rollers will have small grooves in them from wear. This will slightly accelerate the wear on the cam until both surfaces match.
As far a cam removal goes. Measure the lenght of the new cam. Measure the cam lenght from water pump face forward. that is the room you need to get the cam out. All cars are made slightly different. So that will give you a rough guide. Remember the cam needs to come out square to the bearing and cannot come upwards until it clears the last bearing.
Check the price of a felpro top end gasket kit from engine masters. Its normally cheaper than buying the gaskets separtely.
Hope that helps
Bender