splicing wire

hello new guy here with a couple queations. i am replacing the ford/code alarm r/s on my 08 f250 with a code srt9000 alarm r/s. the older alarm r/s was in one of my other vehicles and had it put into the 08 ford. i decided to get a two way paging alarm  and wanted to do the install myself  so i removed the old one and to my surprise the brake light input  splice at the brake switch  was all but hanging on (brake light wire cut most of the way through and connection not soldered )  it was a fun job repairing that , probably the hardest connection to get to. btw i soldered that connection, its secure for now  but that wiring allways moves and wondering if that joint will eventually crack  because of movement?? also the rest of the splices into the wiring only involve a small (1/8 in.) insulation removal with the copper parted in the middle, accessory wire fed through and wrapped around, no solder,no silicone sealer, just tape. i would like to remove 1/4 to 3/8 of insulation to leave room for soldering the connections but want to do a neat job. is their a special tool ror removing the insulation or just automatic wire strippers making a few cuts and using a razer knife to slice across and removeng the insulation?? i have the alarm mostly wired in , not powered up yet, the connectiones are for the most part temp. untill i know it all works right.... thanks !    bill 

15 dollar autostrippers from nh.  you can solder those connections in seconds.  3m super 33+ stays in place in heat and cold, but its more expensive than other tapes.