I figure you are referring to an L16? well I have seen an L20b in a thouee but used a side mechanical waterpump from a boat, this was in a very rusty vb10 I found at some wreckers 25 years ago which also had a big bonnet scoop to clear the bonnet area. It can be done better using an L16 bottom end bored to 85mm with L18 crankshaft and Z18et head, that way you get legally an L18 capacity stamped L16 block and 2.5 inches lower head from the Z series and factory turbo everything and I suspect using the short 78mm stroke L series crank you can easily modify the oil pan to remove its extra depth and all in all make it as tall as an A15 engine providing you use an electric side or mechanical side waterpump.
 
This will be a pollution free engine if you use an early 1600 block from 1972 and pre that date and will go like the clappers with no need for cat converter and plenty of five speed box choices.

Thanks for the reply's.
 
Thats heaps good coz I just bought one . 
 
I will post pictures of my car soon but yeah thanks for the help!

go the A series Mazda head deal....
 
(thats your tap in Pro D)