[Marv D]

You can not get the cam out without pulling the lifters, plain and simple.
I don't build motors with flat tappet cams any more at all, but... I will have to disagree with a lot here in saying the pause in breakin isn't going to automatically spell the demise of a cam. Breakin above 2000rpm is simply to allow the 'sling' of oil off the rotating assembly onto the cam to cool things during breakin, and to also pump lots of oil up into the heads so it gets a wash of oil from above. There is no 'magic' in the breakin rpm as far as 'surface speed' of the lifter and cam lobe, or every cam would need a different breakin rpm with different lobe diameters. Besides think of this,, a drill will burn up if you spin it too fast even if your using a good cutting lube right, but drill slow and steady and the lubricant will protect the bit. Same basic thing with a lathe and cutting edge. SPEED kills! To a point that's basically what were doing in cam breakin,, keeping the flow of oil across the face of the lobe and lifter to keep it cool while the two hardened faces fine a happy medium. Yes there is some reason for the surface speed of the two components, but a stop-start in the total breakin time hasn't been a issue for me, ever. Besides, the flat tappet cam lobe is ground on a slight angle so it 'spins' the lifter and doesn't 'grind away' at the same point of the lifter face. Add a bit of cam walk front to back and there is no reason I can see that a start-stop breakin is a problem AS LONG AS a quality lube and supplement in todays oil is used.

And THAT is the key to your dilemma on what to do IMO. Unless you run a 'real' oil like the $15 a quart off road / racing only oil in this motor for the life of the cam ( 5 qts and a filter for about $80 per oil change x 3 for the first 500 miles) ,, I don't expect ANY flat tappet cam to survive breakin, OR life in stop-go traffic. If you have any kind of performance cam, and the matching springs that it is 'supposed' to have, you need to R&R them for a light breakin spring (so add the cost of breakin springs to the list)
How is a flat tappet cam cost effective? And all this is ASSUMING you don't loose the cam and distribute debris all through the bearings trashing your new rotating assembly. (add a $500-$3000 risk here)

$1000 will get you a nice streetable hydraulic roller cam, a set of SpeedPro 'retro-fit' hydraulic roller lifters, correct length CM pushrods, Springs, and a set of good roller rockers. THEN you can run any of the API starburst graded oils and not worry about it.

Add up how many $80 oil changes you will do in 50,000 miles vs $25 oil changes with a hydraulic roller. Things start to pay for themselves (at least that's how I justified it to my wife LOL)