Power Query multiply rows of one table by row of another

Hi I am trying to replicate in power query what in excel could be ;

   =MMULT(Table32[@[One]:[Three]],Table4[Amount])*[@Units]

I have managed this but it took a lot of nesting list transformation, I have include a version where I named all the steps individually for clarity

let
    Source = Excel.CurrentWorkbook(){[Name="Table3"]}[Content],
    rechead = ( tax [tax]),
    startlist = List.Transform(  Table.ToRows(  Source ),
(x)=> List.Skip( List.RemoveLastN( x ,1) ,1) 
),
    ziplist = List.Transform(  startlist, (x)=>  List.Zip ( { x, tax [Amount] } ) ),
 product = List.Transform(  ziplist, (x)=>  List.Transform( x , (y)=>  List.Product(y) )),
    sum = List.Transform(  product, (x)=> List.Sum( x ) ),
    result = List.Transform( List.Zip(  { sum, Source [Units] } ), (x)=> List.Product( x )  ),
    Custom3 = result
in
    Custom3

if anyone has any ideas on simplifying this I would like to know, I have thought of using records, but have not tried yet.

Richard