Someone asked about this the other day so here's a small write up after donig mine the other day. Both are pretty easy.
Located towards the back of the head around no.4 cylinder on the drivers side and on top of the head. Looks fiddly but not hard to get to. I removed the black steel plate that forms a protective cover for the overflow tube on top of the injectors and also forms one of the clips for the plastic engine cover, which of course you removed first. Steel plate is held in place by 2 torx bolts requiring an E10 socket. Then remove the plug off the cam sensor. It has a press lock on top like most plugs so you have to depress the lock tab and pull towards drivers side. Holding it in the head is an E8 bolt on the inside towards the injectors. I suggest before removing it to give the area a good clean. I sprayed it with carby cleaner then got a rag in there best I could to wipe any oily dust away then a good blow with the compressor. Once bolt is out it just pulls out. Replacement is simply a reverse of the installation procedure.
I bought a torx kit from Trade Tools that was very comprensive with all female sockets for the external torx bolts, male torx that use a socket drive and a set of right angle male torx a bit like an allen key. The only thing wrong in my view is the E10 and up sockets are 3/8 drive whereas I think the E10 should still be 1/4 drive. I could just get in there with my 3/8 ratchet but a 1/4 would be much better.
Crank sensor. This is plugged into the bell housing just above the starter motor. If you look through the gap in the manifold just behind the fuel filter you will partially see it, although the swirl motor might be blocking your view a bit as mine is removed. You may get access by removing the fly by wire throttle sensor but I have stuff bolted to it and you ahev to remove the wiper cowl to get the other bolts to get it out. I got down under the car
and came up between the body and the upper control arm. Again it's fiddly cause you have to press the lock tag while pulling the plug and you have to push up but it will come with patience. Don't worry too much about the plug it is rectangular with one end rounded so can only go back on one way and is easy to feel. The sensor is held in by a single E8 torx bolt. This was easy enough to undo with a small 1/4 socket with a 50mm extension. You are doing this all by feel but whilst tight and a bit frustrating it's not too bad. You could always look at undoing the bolt first and holding the sensor whilst undoing the plug as you can probably see it just beside the starter when unbolted. I could get at the wiring plug reasonably easily to give it a clean with contact cleaner and blow dry with the air gun. Installation same as above.
Don't be afraid of doing either of these jobs as there are far harder jobs to do on the 2.7 than these 2 sensors.( as I can detail in replacing the belt pulleys)