I need to replace a couple of casement windows. What is the right way to flash them? Everything I have read (like this great FH article: http://www.finehomebuilding.com/PDF/Free/021197054.pdf)

assumes the presence of housewrap to flash over. Does typar tape even stick to wood? Or should I just caulk the sides and top? What would the flashing even do on my house?

Also, what is your opinion of premade sill pans like Jamsill? The FH article uses a beveled piece of siding and flashes over that.

Thanks!

Pre-made sill pans are nice but are typically used in new construction applications. How much of the siding will you be removing?

I would like to remove as little siding as possible. Obviously I will remove the outside trim, which should give me most of the room I need for the flashing. Worst, case I may have to sawzall a few nails to get the flashing to be wide enough.

So something like this:
http://www.tarcoroofing.com/pdf/LB_Door_&_Window.pdf
should work well over wood.

I can use a beveled piece of siding instead and not caulk the bottom of the window.

Thanks again!