speaking for Mobile home services :
1] yes you have to run 4 conductor cable but make sure you sized properly for 200 amp service
1A] is that correct the distance is 100 Feet ? i am not sure if your local/ state code do allow that far most useally are less than 35 feet away from Mobile home
2] it will be wise to run new ground rods after you change the meter pedstal or socket and run #4 [ for 200 amp service]
2A] best way is make new concrete pad to support new meter base
3] check with your local code and POCO regulations reguarding with meter socket postion
4] it will be wise idea to run new 2 inch pvc conduct underground to below of the Mobile Home near the power entrince point the reason why is that because if the cable get damaged or something screw up it is eaiser to replace with out digging in the ground espcally where the area have hevey frost [ ya know how hard to dig in frozen ground ]
i am sure few other can chime in with more answer in here
Merci , marc
