neil g

my head gasket blown so had head welded and skimmed car was parked up for mouths due to ill health now have ill engine i,m trying to to sort getting a m8 to help me but think hes going to kill the engine as it dont sound right to me number 4 piston dosnt move side to side on the rings bore is rusted rust is on top of the ring pistons move up down ok bit hard by hand when pistons at top i was going to take no 4 piston out to check clean or change rings my m8 said i would have to change conrod shells ?? if taking it out also lightly wet and dry sand the bore or wet dry the bore use something thin to clean top ring pour piraffin down to clean inside rings i,ve taken off the sump every where is has oil water mix on it creamy he wants to blast it with pariffin inside engine on crank !! but i have my douts as then the shells would be dry on start up and damage all the shells i,ve got some oil mixer to clean internal chanels of old burnt oil and sludge cleaning what i can off the car i,m not letting him touch the car till i know for deff what is what plz help