I would think that the kind with a hand knob on top would be your best in reaching over the spring since the room you have around it is limited.
When replacing the cam, be sure to get all your rocker arm assemblies back in place with the bolts finger tight, then tighten them down evenly, you can strip threads, or even break the cam if you're not careful. The key is even pressure up and down both ends of the cam.
'01 C Class, Six Speed
'84 Euro 240D, manual, 533K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in