Hello this my first post, I have 1999 Regal 6.8 ventura with a 5.7 mag mpi / Bravo 3 450 hours used in salt water. I was having over heating problems which was trouble shot down to the water tube in the transom assy strangled by corrosion. I put the boat in the shop for repairs due to the fact that the drive and engine had to removed to replace the tube, I also wanted the trim limit/sensor replaced. After the engine was removed the mechanic found that the anti knok sensor had been leaking and needed to be replaced when the sensor was removed a 2" divit of rust/block came out with it and had a small crack which where the leak came from. The shop said the sensor cant be reinstalled and the block is comprimised. They are recomending engine repower with a mercruiser rebuilt long block. So my 1300.00 repair has topped 6000.00. has anyone else had this type of problem and is there a better option. I have had the boat since 2003 with few problems other than reg maint. any thoughts would appr.