[Hottrucks]

well this is up my ally and these guys have covered most of the importtant stuff..but heres a trick I learned from years of rebuilding boats and the lower gear boxs, and props

A piece of copper flashing under your weld helps in the burn though, it disapates some of the heat while holding the multon aluminum up in place but it won't stick to it...also they have a wax that you put on after your done to stop your grinding flap from cloggin up

Now to address your transom issue your probably trying to add about 5" to the height to go from a short shaft motor to long...???...there are some simple ways to do this without welding ( truth is the welds are going to break because of the stress/vibartion trust me). probably the best and easyest way is to add a peice of 2x6 and cut it as a filler the same thickness/shape as the transom...have a piece of aluminum cut and bent to go up the transom and over the 2x6 and back down the inside...use 3M 3200 and stainless bolts use the 2 exsiting bottom holes and though bolt it there using a plate inside as a backer....now when you mount the motor the 2 new bottom bolts will go though also the top clap will hold the top...add 2 transom brackets from near the top to the stringer and call it done...keep in mind the motor pushs on the bottom of the bracket not the top..if you have any more questions or I can help just let me know