New window install

http://www3.telus.net/martik/window.jpg
I want to install a vinyl nail-on flange window WITHOUT removing all the siding first. I was thinking of sawing thru the both the cedar siding and the old flange, removing the window then prying the bottom and one side, remove the other side and top and finally all the old flange behind the siding. To replace the window, I would cut off the flange on one side, then angle the bottom flange in.
The reason I cannot easily remove all the siding is because the bottom row pieces go behind the header for the sundeck not to mention punching thru all the nails is alot of work. I don't want to go with wide flange 'reno' windows.
Which tool would work best for this job? A skill saw is too big for a neat cut, maybe a reciprocating saw. I would prefer not to remove for the 1/8" around the perimeter.
Any other suggestions welcomed
Thanks
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Removing and reinstaling Cedar Shakes is easy, reinstal is just nailing below the one above, remove with prybar and twist.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Many of the vertical cedar siding boards are well over 10' long and split easily when prying. That's why I punch the nails thru.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Martik wrote:

out the wood around it not to mention the the interior finishes. Put it in properly or pay to do it over AND repair the damage in a few years.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thanks, good point. I replaced a slider 3 years ago and some water did get thru when driving rain pelted that side of the house. I caulked the joints in the siding all the way up to the soffits and it stopped. The original windows were installed w/o any flashing or caulking around the flange - guess I have been lucky. I will do both on any new ones I install and I won't remove that side flange.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.