Chris,
You have nearly as much to do as me!! No doubt you will get most of it done as four of the items are all related to the dash. I caution you to get some wire markers and mark every wire you disconnect!! I assure you that it is not fun tracing all the wiring down. If your Sonic is like mine, there are two wiring harnessess....one down each side of the boat. You will find that BOTH are connected to each fused connection even though only one wire is used. This is a potential for disaster and a wire not used.... if grounded can blow the fuse feeding the other side of the boat! I disconnected all the actually unused wiring and all my dash lites are much brighter now. One other thing that you can do to massively improve the dash is to put in at least a 6 ga. battery & ground lead & connected to Buss bars (add them) under the dash & wired to the battery switch. Use these buss bars as the battery source for all your switches and accessories and as the main ground buss. This can clear up a lot of things, it did for me.